Extracts from Pelargonium sidoides. Inhibit the Growth of Bacteria and Fungi

Abstract

Pelargonium sidoides. DC (Geraniaceae) is a medicinal plant used by the people of the Eastern Cape, South Africa, for the treatment of various diseases in man and livestock. Acetone and methanol extracts of the shoot and root of the herb were investigated for antimicrobial activity against 10 bacterial and 5 fungal species by the dilution method on solid agar medium. With the exception of Staphylococcus epidermidis., extracts obtained from both solvents demonstrated significant activity against all the Gram-positive and two of the Gram-negative bacteria tested in this study. The extracts also showed appreciable inhibitory activity against all the fungal species tested with inhibition ranging from 52.5% on Aspergillus flavus. to 82.5% on Mucor hiemalis. at 5 mg ml^?1, the highest concentration tested in the study. The ability of the extracts of this plant to inhibit the growth of several bacteria and fungi is an indication of the broad-spectrum antimicrobial potential of P. sidoides. that further validates the use of this plant for the treatment of various ailments by the people of the Eastern Cape.     

Antimicrobial activity of Hermannia incana

Hermannia incana Cav. (Sterculiaceae) is a prostrate herb used to treat stomachache and diarrhea, and as an emetic by the people of Eastern Cape Province, South Africa. Acetone, methanol, and water extracts from the leaves and roots of the plant were investigated for antibacterial and antimycotic activities. The methanol extracts of the plant showed appreciable activity against Gram-positive and Gram-negative bacteria at concentrations ranging from 0.5 to 7?mg/mL. The acetone and water extracts of both the leaves and the roots showed moderate activity against Gram-positive bacteria and less activity against Gram-negative bacteria. All the extracts inhibited the growth of the fungi Aspergillus flavus, Aspergillus niger, and Mucor hiemalis with growth inhibition based on MIC ranging from 54% to 96% at 0.1-?10?mg/mL. None of the extracts suppressed the growth of Candida albicans at the maximum concentration (10?mg/mL) tested. This study has pointed to the potential application of Hermannia incana as a bacteriocide and fungicide.     

Medicinal Potential of the Root of Arctotis arctotoides.

Abstract

The antioxidant and antimicrobial activity of the acetone, methanol, and water extracts from the root of Arctotis arctotoides. (L.f.) O. Hoffm (Asteraceae) were assessed in an effort to validate the medicinal potential of the subterranean part of the herb. The antioxidant activities of acetone and methanol extracts as determined by the ABTS, DPPH, and FRAP methods were higher than that of water extracts. The extracts showed significant activity against both Gram-positive and Gram-negative bacteria. The strongest activity was found in the acetone extract on Bacillus cereus., Staphylococcus aureus., Micrococcus kristinae., and Streptococcus pyrogens. with an MIC of 0.1 mg/mL. Although not completely fungicidal, these extracts showed significant growth inhibition against all the fungi tested. Antioxidant and antimicrobial activities of the extracts were strongly correlated with total phenols and to a lesser extent with their flavonoids and proanthocyanidins contents. This study has validated the medicinal potential of the underground part of A. arctotoides..     

Synthesis and in?vitro antimicrobial activity of benzo[b][1,4]thiazin-3(4H)-ones via smiles rearrangement

New benzo[b][1,4]thiazin-3(4H)-one derivatives (compounds 12a–p) were synthesized via Smiles rearrangement and assayed in vitro for their antimicrobial activity against Gram-positive, Gram-negative bacteria and fungi. The antimicrobial activity of the benzo[b][1,4]thiazin-3(4H)-ones showed, on the whole, potent toward all tested Gram-positive and Gram-negative microorganism (minimal inhibitory concentration ranging from 16 to 64 μg/ml), whereas weak effectiveness was exhibited against fungi. Data obtained suggested that 12g, 12i, and 12o exerted the best antibacterial activity against Gram-positive bacteria and compound 12b demonstrated the best inhibition of Gram-negative bacteria. These observations provide some predictions to design further antimicrobial active compounds prior to their synthesis following with molecular modeling studies.     

Antimicrobial Activities of Fruits of Crataegus. and Pyrus. Species

Abstract

The antimicrobial activity of the ethyl acetate extracts from fruits of Crataegus tanacetifolia., Crataegus x bornmülleri., Pyrus communis. subsp. communis., and Pyrus serikensis. (Rosaceae) were investigated by the agar-well diffusion assay, and the extracts exhibited antimicrobial effect against most of the bacteria and all of the yeasts tested. Although the plants differed in their activities against the microorganisms tested, the extracts of C. x bornmülleri. and P. communis. subsp. communis. displayed no antifungal activity against the fungi tested. P. serikensis. extract inhibited the growth of all bacteria tested but not Aspergillus niger., Aspergillus parasiticus., Aspergillus citri., and Aspergillus fumigatus.. In conclusion, P. serikensis. was the most active antimicrobial plant. Particularly, P. serikensis. extract showed significant antifungal activities and could be used as an antimicrobial agent in new drug therapy.     

ANTIMICROBIAL AND PHYTOCHEMICAL STUDIES ON THE LEAVES OF PHYLLANTHUS SINGAMPATTIANA (SEBASTINE & A.N. HENRY) KUMARI & CHANDRABOSE FROM INDIA

Leaves of Phyllanthus singampattiana, locally known as Aathuchadai by the Kanis of Tamil Nadu in India is consumed for curing jaundice, diarrhea and dysentery. Preliminary phytochemical analysis revealed the presence of flavones and triterpenes in all the solvent extracts, coumarins and steroids in hexane and chloroform extracts, quinine, alkaloids, lignins and phenols in chloroform and methanol extracts and proteins, saponins, starch, sugar and tannin in methanol extract. Isolation yielded friedelin, epi-friedelinol, n-octacosanol, α-amyrin, β-sitosterol, luteolin and β-sitosterol-3β-D-glucopyranoside. The aqueous and solvent extracts when tested against 11 gram-negative and 2 gram-positive bacteria and 3 fungi expressed activity to most of the organisms. Activity was not recorded for hexane extract, against A. niger and A. flavus (except methanol extract) and against S. aureus in lower concentration of chloroform extract. Methanol extract showed more activity amongst all the solvent extracts, particularly remarkable activity recorded against gram-positive bacteria. Activity against diarrhea and dysentery causing organisms such as A. hydrophila, E. aerogenes, K. pneumoniae, P. vulgaris, S. enteritidis, V. cholerae, V. parahaemolyticus and V. vulnificus substantiated the claims of the ethnic uses. Activity against C. albicans indicates the possibility to develop drugs for skin diseases.     

Synthesis and antimicrobial activity of pyrimidinophanes containing a uracil moiety and a bridging sulfur atom

Pyrimidinophanes containing one 5(6)-alkylsubstituted uracil moiety and a 10-or 12-methylene bridge including a sulfur atom were synthesized. The bridging S atoms of the macrocycles were converted to sulfonium groups by interaction with para-toluenesulfonate methyl or nonyl esters. The resulting amphiphilic pyrimidinophanes were tested for bacteriostatic and fungistatic activity against Gram-positive and Gram-negative bacteria and fungi. Amphiphilic pyrimidinophanes with 5-decyl-6-methyluracil moieties had high levels of bacteriostatic activity against Gram-positive bacteria. The minimum inhibitory concentration of the macrocycle containing a methyl group in the sulfonium grouping against Staphylococcus aureus was 0.75 !g/ml. These data are of value in seeking new highly effective antimicrobial agents.     

Antibacterial and Antifungal Activities of Volatile Oils from Zanthoxylum Rhoifolium. Leaves

Abstract

The volatile oil extracted from Zanthoxylum rhoifolium. Lam (Rutaceae) leaves was tested to verify its antimicrobial activity efficacy against six types of different high-virulent Gram-negative bacteria isolated from clinical material and against three different types of fungi (two yeast and a filamentous one). Some results were different from those observed in the literature, and these differences might have occurred due to seasonal, geographic, or nutritional variations of the plants. Nevertheless, the volatile oil was found to be very efficient against Salmonella enteritidis. and Shigella sonnei., bacteria responsible for diarrhea and for a huge number of deaths. Regarding the fungi, a great capacity of the volatile oil in inhibiting the growth of Aspergillus flavus. was found, although it does not affect Candida tropicalis. and Candida guilliermondii. growth.     

Antimycotic Activity of 20 Plants from Colombian Flora

Abstract

The antifungal activities of 65 extracts were evaluated through the agar well diffusion method in 22 plant samples from the Ucumari Natural Regional Park (UNRP). These samples belong to 20 plant species related to the following botanic families: Asteraceae, Euphorbiaceae, Melastomataceae, Podocarpaceae, Rubiaceae and Solanaceae. The plant extracts were obtained in hexanes, dichloromethane and methanol. The 65 extract samples were tested against pathogenic fungi Aspergillus fumigatus (ATCC 1022), Candida albicans (ATCC 18804) and Fusarium solani (ATCC 11712). Ketoconazole was used as positive control. The methanol extracts from Solanum spp. (FJR 3155) and Tibouchina grossa exhibited the greatest inhibitory activity against the three fungi tested, while the methanol extracts from Hyeronima macrocarpa, Miconia lehmannii, and Sapium stylare inhibited two of the fungi assayed. The dichloromethane extracts from Miconia lehmannii Cong, Lycinathes acutifolia and Solanum spp. (FJR 3155) inhibited two of the three fungi tested, while the dichloromethane extracts from Cinchona pubescens Vahl and Palicourea spp. (FJR 3182) inhibited one of the three microorganism tested. Only one of the hexane extracts produced activity against the three fungi tested.     

Antimicrobial activity of crude epicarp and seed extracts from mature avocado fruit (Persea americana) of three cultivars

The epicarp and seed of Persea Americana Mill. var. Hass (Lauraceae), Persea Americana Mill. var. Shepard, and Persea americana Mill. var Fuerte cultivars of mature avocados (n?=?3) were ground separately and extracted with both absolute ethanol and distilled water. Extracts were analyzed for antimicrobial activity using the microtiter broth microdilution assay against four Gram-positive bacteria, six Gram-negative bacteria, and one yeast. Antimicrobial activity against two molds was determined by the hole plate method. The ethanol extracts showed antimicrobial activity (104.2–416.7 μg/mL) toward both Gram-positive and Gram-negative bacteria (except Escherichia coli), while inhibition of the water extracts was only observed for Listeria monocytogenes (93.8–375.0 μg/mL) and Staphylococcus epidermidis (354.2 μg/mL). The minimum concentration required to inhibit Zygosaccharomyces bailii was 500 μg/mL for the ethanol extracts, while no inhibition was observed for the water extracts. No inhibition by either ethanol or water extracts was observed against Penicillium spp. and Aspergillus flavus.     

The antimicrobial activity of garlic and onion extracts

Aqueous extracts of garlic (Allium sativum) and onion (Allium cepa) were tested for activity against Gram-positive organisms, Gram-negative organisms and fungi. A significant growth inhibition was shown by most of the organisms, tested at random. A quantitative assessment of the activity was carried out by determining the minimum bacteriostatic and bactericidal concentrations of the extracts against Gram-positive and Gram-negative organisms. Garlic extract showed greater activity as compared to the extract of onion. The activity of the garlic extract on the mouth flora of volunteers was then investigated. A mouth wash containing 10% garlic in quarter Ringer solution produced a drastic reduction in the number of oral bacteria.     

Synthesis of benzo[b][1,4]oxazin-3(4H)-ones via smiles rearrangement for antimicrobial activity

The benzo[b][1,4]oxazin-3(4H)-one derivatives, 1a–p, carrying F, Br, and Cl on the benzene ring, or benzyl, cyclohexyl, n-hexyl, and tetrafuryl methylene groups attached to nitrogen atom were synthesized via Smiles rearrangement and assayed in vitro for their antimicrobial activity against Gram-positive, Gram-negative bacteria, and fungi. The antimicrobial activity of the benzo[b][1,4]oxazin-3(4H)-ones showed, on the whole, potency toward all the tested Gram-positive and Gram-negative microorganism (MIC ranging from 16 to 64 μg/ml), whereas weak effectiveness was exhibited against fungi. Data obtained suggest that fluorine atom in the compounds, 1c, 1f, 1i plays an important role in enhancing the antimicrobial properties of this class of compounds. These observations provide some predictions to design further antimicrobial active compounds prior to their synthesis according to molecular modeling studies.     

Antimicrobial Activities of Malaysian Plant Species

Antimicrobial activities against reference Gram-positive (Staphylococcus aureus, Enterococcus faecalis) and Gram-negative (Escherichia coli, Pseudomonas aeruginosa) bacteria and Candida albicans were tested on 191 plant extracts obtained from more than 30 families of plants found in the state of Sabah, Malaysia. The plant extracts were tested by a disk-diffusion technique in which antimicrobial activity was evaluated based on the ability of the plant extracts to diffuse through agar to affect the target organisms. The extracts of Callicarpa erioclona Schau. (Verbenaceae), Callicarpa farinosa Roxb. (Verbenaceae), Sphonodesma friflora Wright (Verbenaceae), and Homalium panayanum F. Villar (Flacourticeae) exhibited antimicrobial properties worthy of further investigation.     

Biological Activity of Extracts in Relationship to Structure of Pure Isolates of Abutilon indicum

The present investigations were undertaken to determine the antibacterial and antifungal activity of the crude extract (CE) of plant parts of Abutilon indicum L. (Malvaceae) in relation to the structure of all previous isolates active and inactive against three Gram-negative bacteria, four Gram-positive rods, and three fungi using agar diffusion method. The results suggested some importance and influence of the hydroxyl groups in the isolates structures such as steroids, flavonoids, glycerides, and coumarins on the activity. The material tested had exhibited excellent activity compared to some of the typical antibiotics against both Gram-positive and Gram-negative bacteria. In summary the results obtained with this plant extract may be considered very promising, indicating the potential for obtaining new antimicrobial agents.     

Antimicrobial activity of Alepidea amatymbica

Alepidea amatymbica Eckl. & Zeyh (Apiaceae) is a medicinal plant traditionally used for the treatment of various diseases including asthma, influenza, and diarrhea in South Africa. The antimicrobial activities of the acetone and methanol extracts of the leaf, stem, rhizome, and root of the species were assessed in an effort to validate the traditional medicinal uses of this herb, especially for the treatment of infectious diseases. Ten bacterial and three fungal species were bioassayed using the agar dilution method. All the extracts demonstrated appreciable activities against three Gram-positive bacteria. These bacteria have been implicated in different respiratory diseases. The inhibitory activity of some of the extracts against pathogens implicated in diarrhea diseases further validated the use of the herb in traditional medicine. Except for acetone leaf extract against Aspergillus flavus and Aspergillus niger, all the extracts showed more than 50% mycotic inhibition with activity ranging from 51.39% on A. niger to 81.11% on Penicillium notatum at 5?mg mL^?1 which was the highest concentration tested in the study. The ability of the herb to inhibit the growth of various bacteria and fungi species is an indication of the broad-spectrum antimicrobial potential of A. amatymbica; this further validates the use of the herb for various diseases by the people of the Eastern Cape.     

Antibacterial Activity in Higher Fungi (Mushrooms) and Endophytic Fungi from Slovenia

Abstract

Discovery and development of new antibiotics is still very important because of the constant appearance of drug-resistant pathogenic bacteria. The broth microdilution test was applied for screening of antibacterial activity in extracts of higher and endophytic fungi. Among tested extracts, three possessed significant antibacterial activity: extracts of mushrooms Amanita virosa. (Fr.) Bertill. (Amanitaceae) and Cortinarius praestans. Cordier (Cortinariaceae) against Pseudomonas aeruginosa. and Staphylococcus aureus., respectively, and extract of endophytic fungus Trucatella hartigii. (Tubeuf) Steyaert (Amphisphaeriaceae) against Enterococcus faecalis. and S. aureus.. The extract of Truncatella hartigii. was further analyzed by one- and two-dimensional thin-layer chromatography, and the position of the active compound was determined on the chromatogram.     

Antimicrobial screening of essential oils and extracts of someHumulus lupulus L. cultivars

The essential oils as well as solvent extracts of 11 hop cultivars, 1 hop variety and a wild type of hop were screened for their antimicrobial activities using the agar overlay technique. The oils were isolated from the cones of the various hop plants by hydrodistillation, the extracts were obtained by soaking the hop cones in chloroform. The oils and the extracts showed activity against the Gram-positive bacteria (Bacillus subtilis andStaphylococcus aureus) and the fungus (Trichophyton mentagrophytes var.interdigitale), but almost no activity against the Gram-negative bacterium (Escherichia coli) and the yeast (Candida albicans) used in the screening. The peak area percentages of the main volatile components and the contents of the bitter acids of the extracts were determined for all cultivars using chromatographic methods.     

Chemical constituents and antimicrobial activities of the essential oils from Sedum pallidum var. bithynicum and S. spurium grown in Turkey

Chemical compositions of the essential oil of Sedum pallidum Bieb. var. bithynicum (Boiss.) and S. spurium Bieb. (Crassulaceae) from Turkey were investigated by GC-MS, and antimicrobial activity of the oil samples were assessed against Gram-positive/negative bacteria and yeast-like fungi. Thirty-eight and thirty-five components were identified in the essential oils and the main components of these species were found to be caryophyllene oxide from S. pallidum var. bithynicum and hexahydrofarnesyl acetone from S. spurium in the ratios of 12.8% and 15.7%, respectively. The isolated essential oils of the plants showed low antimicrobial activity against Gram-negative/positive bacteria and yeast-like fungi, having the MIC values of 500-2000?μg/mL. Antibacterial activity was not observed against Bacillus cereus.     

Antibacterial activity of two phloroglucinols,flavaspidic acids AB and PB,from <Emphasis Type="Italic">Dryopteris crassirhizoma</Emphasis>

The antimicrobial effect of solvent extracts from the rhizome of a thick-stemmed wood fern (Dryopteris crassirhizoma) was evaluated and its phloroglucinol components, flavaspidic acids PB and AB. Flavaspidic acids PB and AB were isolated from the D. crassirhizoma rhizomes by methanol extraction, followed by silica gel and Sephadex LH-20 column chromatography. The chemical structures were characterized by spectral techniques, including ESI-MS, UV, ¹H- and ¹³C-NMR spectrum analysis. When the antimicrobial activity of the extracts and compounds was tested by the paper disc method, the extracts and compounds were highly active against Gram-positive bacteria, such as methicillin-resistant Staphylococcus aureus KCTC 1928 (a MRSA bacterium), Streptococcus mutans and Bacillus subtilis. The extracts and compounds were not active against fungi and chlorella. Our study revealed that the antibacterial activity of samples from D. crassirhizoma was mainly related to the flavaspidic acids.     

Antimicrobial Activity of Goniothalamus Grandiflorous

The extracts of stem bark, leaves and flowers of Goniothalamus grandiflorous were screened against six Gram positive and six Gram negative bacteria, a parasite, and four fungi. All extracts were found to be active against all the bacteria and some fungi. The flower and the leaf extracts exhibited a superior level of antibacterial activity. The flower and bark extracts were active against T. mentagrophytes. Isoaltholactone isolated from the leaves, was the active principle and exhibited a good level of activity against the tested organisms.