Antibacterial activity in Actinidia chinensis, Feijoa sellowiana and Aberia caffra

The antibacterial activity of extracts from various parts of plants (leaves, fruits and stems) was studied in Actinidia chinensis, Feijoa sellowiana and Aberia caffra. These are tropical plants used for food. The fruits (subdivided into skin, pulp and seeds), leaves and stems were separately extracted and tested, in triplicate, against eight Gram positive and Gram negative bacterial strains. All the extracts, except from the leaves of A. caffra, showed activity against all the strains employed. Inhibition of bacterial growth was tested against Na-cefotaxime, benzyl penicillin and tetracycline. The antibiotic activity of fruit resides essentially in the seeds. The antibacterial activity of extracts from vegetative plant parts was generally less active that from fruit extracts. The minimum inhibiting concentration (MIC) and minimum bactericidal concentration (MBC) were determined for all the extracts and showed exclusively bacteriostatic activity.     

Anti-Mycobacterial Screening of British Columbian Medicinal Plants

One hundred methanol plant extracts were screened for antibiotic activity against Mycobacterium tuberculosis and Mycobacterium avium. Nineteen extracts exhibited some activity against M. tuberculosis and 16 extracts showed some activity against M. avium. Thirteen of these 19 active extracts were traditionally used by First Nations peoples to treat tuberculosis. Extracts made from Heracleum maximum (Umbelliferae) roots, Moneses uniflora (Ericaceae), aerial parts, and Oplopanax horridus (Araliaceae) inner bark completely inhibited the growth of both organisms at a concentration equivalent to 20 mg dried plant material/disc. Extracts of Alnus rubra (Betulaceae) bark and catkins, Empetrum nigrum (Empetraceae) branches, Glehnia littoralis (Umbelliferae) roots, and Lomatium dissectum (Umbelliferae) roots completely inhibited the growth of both M. tuberculosis and M. avium at a concentration equivalent to 100 mg dried plant material/disc.     

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.     

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.     

Screening for Anticancer Agents from Sonoran Desert Plants:A Chemical Ecology Approach

This study evaluates the potential benefits of using ecology-based theories of plant chemical defense when screening plants for pharmaceutical activity. Extracts from 63 Sonoran Desert plant species representing 26 families were screened in microtiter/optical density–based assays against a cervix epithelial carcinoma cell line (HeLa) and mouse fibroblast cells (3T3). In HeLa cytotoxicity assays, 34 of 63 species (54%) showed significant inhibitory effects. Nine of these active extracts were significantly less toxic to a noncancerous mouse fibroblast cell line (3T3) and, thus, showed potentially cancer specific activity. Using the plant apparency/predictability hypothesis as a theoretical basis, this study used plant growth habit (e.g., annual, herbaceous perennial, woody perennial, evergreen) as an indicator of plant predictability, and hence likelihood of having well-established chemical defenses. This approach led to predictions that may be useful in locating plant species that produce biologically active secondary metabolites. As predicted, extracts from evergreen species exhibited the highest activity with 41.7% of extracts showing inhibition, followed by woody perennials (37.3%), herbaceous perennials (35.7%), and annuals (23.3%). Average percent inhibition was significantly higher in the evergreen and woody perennial groups as compared to other growth forms. These results support predictions made by the plant predictability hypothesis and illustrate the potential value of incorporating ecological theories of plant chemical defenses in plant screening efforts.     

Screening of Ethanol, Petroleum Ether and Chloroform Extracts of Medicinal Plants, Lawsonia inermis L. and Mimosa pudica L. for Antibacterial Activity

Organic extracts (ethanol, petroleum ether and chloroform) of two medicinal plants Lawsonia inermis L. and Mimosa pudica L. were proven for antibacterial properties against 15 Gram-positive and Gram-negative human pathogenic bacteria. Among the three types of extracts tested, ethanol extract was found to possess maximum antibacterial activity. The diameter of the zone of inhibition of bacterial growth showed that Gram-negative bacteria are more sensitive than Gram-positive bacteria to plant extracts. Between the two plants species studied, Lawsonia inermis extract showed more antibacterial activity compared to Mimosa pudica extract.     

Three kinds of antibacterial substances from Lentinus edodes (Berk.) Sing. (Shiitake, an edible mushroom)

Three kinds of antibacterial substances were extracted by chloroform, ethylacetate or water from dried Shiitake mushrooms (Lentinus edodes). These substances possess efficient antibacterial activities against Streptococcus spp., Actinomyces spp., Lactobacillus spp., Prevotella spp., and Porphyromonas spp. of oral origin. In contrast, other general bacteria, such as Enterococcus spp., Staphylococcus spp., Escherichia spp., Bacillus spp., and Candida spp. were relatively resistant to these substances. Chloroform extracts had bactericidal activity against both growing and resting bacterial cells of S. mutans and P. intermedia, whereas the other two extracts showed bacteriostatic activity against both growing and resting bacterial cells of S. mutans and resting bacterial cell of P. intermedia. The antibacterial activity of chloroform extracts and ethylacetate extracts were relatively heat-stable. The water extract was heat-labile.     

Antioxidant,cytoprotective and antibacterial effects of Sea buckthorn (Hippophae rhamnoides L.) leaves

The present study was carried out to investigate the antioxidant, cytoprotective and antibacterial effects of aqueous and hydroalcoholic extracts of Hippophae rhamnoides L. (Sea buckthorn) (SBT) leaves by using various invitro systems and analysis of marker compounds by reverse phase-high performance liquid chromatography (RP-HPLC). The chemical composition of the leaf extracts was quantified by colorimetric reaction in terms of total phenol and flavonoids contents. Further, some of its bioactive phenolic constituents, such as quercetin-3-O-galactoside, quercetin-3-O-glucoside, kaempferol and isorhamnetin were also quantified in both SBT leaf extracts by RP-HPLC. The SBT leaf extracts exhibited potent antioxidant activity determined by 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS), 2,2-diphenyl-1-picryl-hydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) assays. Further, both extracts were observed to have cytoprotective activity against hydrogen peroxide and hypoxanthine-xanthine oxidase induced damage to BHK-21 cell line. The SBT leaf extracts showed growth inhibiting effect against Bacillus cereus, Pseudomonas aeruginosa, Staphylococcus aureus and Enterococcus faecalis. These observations suggest that aqueous and hydroalcoholic extracts of Sea buckthorn leaves have marked antioxidant, cytoprotective and antibacterial activities.     

Antibacterial properties of traditionally used Indian medicinal plants

In search of broad-spectrum antibacterial activity from traditionally used Indian medicinal plants, 66 ethanolic plant extracts were screened against nine different bacteria. Of these, 39 extracts demonstrated activity against six or more test bacteria. Twelve extracts showing broad-spectrum activity were tested against specific multidrug-resistant (MDR) bacteria, methicillin-resistant Staphylococcus aureus (MRSA) and extended spectrum beta-lactamases (ESbetaL)-producing enteric bacteria. In vitro efficacy was expressed in terms of minimum inhibitory concentration (MIC) values of plant extracts. MIC values ranged from 0.32-7.5 mg/ml against MRSA and 0.31-6.25 mg/ml against ESbetaL-producing enteric bacteria. The overall activity against all groups of bacteria was found in order of Plumbago zeylanica > Hemidesmus indicus > Acorus calamus > Camellia sinensis > Terminalia chebula > Terminalia bellerica > Holarrhena antidysenterica > Lawsonia inermis > Mangifera indica > Punica granatum > Cichorium intybus and Delonix regia. In addition, these extracts showed synergistic interaction with tetracycline, chloramphenicol and ciprofloxacin against S. aureus and/or Escherichia coli. The ethanolic extracts of more than 12 plants were found nontoxic to sheep erythrocytes and nonmutagenic, determined by Ames test using Salmonella typhimurium test strains (TA 97a, TA 100, TA 102 and TA 104). Based on above properties, six plants-Plumbago zeylanica, Hemidesmus indicus, Acorus calamus, Punica granatum, Holarrhena antidysenterica and Delonix regia-were further subjected to fractionation-based study. Ethyl acetate, acetone and methanol fractions of more than six plants indicated that the active phytocompounds were distributed mainly into acetone and ethyl acetate fractions, whereas they were least prevalent in methanol fractions as evident from their antibacterial activity against MDR bacteria. Gram-positive and Gram-negative MDR bacteria are almost equally sensitive to these extracts/fractions, indicating their broad-spectrum nature. However, strain- and plant extract-dependent variations in the antibacterial activity were also evident. Time-kill assay with the most promising plant fraction Plumbago zeylanica (ethyl acetate fraction) demonstrated killing of test bacteria at the level lower than its MIC. Further, identification of active constituents in each fraction and their additive and synergistic interactions are needed to exploit them in evaluating efficacy and safety in vivo against MDR bacteria.     

Phytopharmaceuticals. Part 1. Antifungal Activity of Selected Iranian and Canadian Plants

Crude extracts from 40 Iranian and Canadian plants were tested for their antifungal activity against several species of Aspergillus, Candida, and Cryptococcus. Of the 40 plant extracts, 26 (65%) showed activity against at least one fungal strain. The extracts with the most wide spectrum of activity were related to Diplotaenia damavandica, Heracleum persicum, Sanguisorba minor, and Zataria multiflora. The high percentage of activity among the studied plants might be attributed to the non-random nature of the selection. A total number of eight factors was used to select the plants in this study. Cytotoxicity test in KB cells was performed on some of the most promising plant extracts. Diplotaenia damavandica and Bunium persicum were found to exhibit the lowest cytotoxicity among the plants studied.     

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.     

Scorpion antivenom effect of micropropagated Aristolochia elegans

Aristolochia elegans Mast. (Aristolochiaceae) has been used to treat scorpion envenoming in Mexican traditional medicine. In vitro studies of the pharmacological activity of raw extracts from A. elegans roots have shown activity against scorpion bite. The aim of the present study was to determine for the first time the antagonistic effect of hexane and methanol extracts of the aerial parts and roots from micropropagated A. elegans plants in a model of isolated guinea-pig ileum contracted by scorpion bite. Results showed that the methanol extracts of aerial organs (74%) and roots (65%) of micropropagated plants have a similar antitoxin activity against scorpion poisoning to hexane extracts of wild plants (65%). These results suggest that using methanol extracts from the micropropagated plant material instead of wild plant root extracts from A. elegans is an alternative for treatment against scorpion bite symptoms, and will contribute to the conservation of this medicinal species.     

Evaluation of the antibacterial activity of Chilean plants traditionally used for wound healing therapy against multidrug-resistant Staphylococcus aureus

Anti-staphylococcal activity of Chilean medicinal plants traditionally used by the Huilliche people for wound healing therapy was evaluated against nine Staphylococcus aureus strains. Three extracts of 26 plant samples (20 species) were evaluated by agar overlay bioautography and MIC determination. Total phenolics and tannins were determined, and the antibacterial contribution of the latter was evaluated. The diffusion assay showed that 17 species were active against susceptible S. AUREUS and that 15 species were active against resistant S. aureus. Removal of tannins from extracts rendered only six species active. MIC-determination showed that 20 extracts had antibacterial activity on all eight strains, and the most potent MIC value was 64?μg/mL. Remarkably, 37 extracts were active against the otherwise multidrug-resistant vanthida strain. Our findings support the wound healing properties of Huilliche medicinal plants and the hypothesis that these plants are promising sources of potential anti-staphylococcal agents towards multidrug-resistant strains.     

Inhibition of Staphylococcus Aureus Mediated by Extracts from Iranian Plants

In order to find new antibacterial agents effective against Staphylococcus aureus, ethanolic extracts of 10 plants were tested. S. aureus (489 samples) were isolated either from healthy carriers (nose and throat) or clinical samples. Out of 489 isolates tested, 98.6% were sensitive to trimethoprim-sulfamethoxazole which was used as the reference antibiotic. From the plant extracts screened for antibacterial activity, Myrtus communis L. (leaves) had the greatest activity, inhibiting the growth of 99% of the isolates. Glycyrrhiza glabra L., Eucalyptus globolus Labill and Menta viridis L., were also active against the isolates inhibiting the growth of 90, 59.5 and 48.7% of the isolates, respectively. All of these extracts were active against the reference strains of S. aureus tested. Saturia hortensis L., Teucrium polium L., and Achillea santolina L., had very little antibacterial activity, while Trigonella foenum graecum L., Echium amoenum Fisch & Mey (flowers) and Juglans regia L. (leaves), had no antibacterial activity against the bacterial isolates.     

Antibacterial activities of some selected plant extracts of local herbal medicines in Lahore-Pakistan

The antibacterial activity of methanol and acetone extracts of five plant extracts being utilized for the cure of different ailments in Pakistan was studied.The extracts of Curcuma zedoaria,Ipomea turpethum,Sphaeranthus indicus,Terminalia chebula and Tricholepis glaberrima were tested against seven different bacterial strains by well diffusion method and microdilution methods.The pattern of zone of inhibition varied with the plant extracts,the solvent used for extraction and organisms tested.Plant extracts(20 mg/mL) were used to evaluate antibacterial activities.The zone of inhibition exhibited by methanol extracts varied between 11 mm and 32 mm while those of acetone extracts varied between 9 mm and 25 mm respectively.The minimum inhibitory concentration(MIC) exhibited by methanol extracts ranged between(18.4-51.1) mg/mL.Overall methanolic extracts showed more activity than the acetone extracts against tested organisms except for S.indicus.The plants were also analyzed for their elemental composition using atomic absorption spectrophotometer to explore natural sources of essential elements that can be utilized for medicinal purposes.     

Evaluation of Antimicrobial Activity of Extracts from South African Usnea barbata

Usnea barbata is a lichen of the Usneaceae family that grows epiphytically on trunks and branches of trees. It is widespread in Hogsback, South Africa. Extracts of the lichen were investigated for antimicrobial activity against 10 bacterial and 5 fungal strains by dilution method on solid agar medium. The extracts showed significant activity against the Gram-positive bacteria with minimum inhibitory concentration as low as 0.1 mg/ml on Bacillus subtilis, Enterococcus faecalis, Micrococcus viradans and Staphylococcus aureus. The acetone extract was the most active while the water extract showed the least activity against the microbes. Our findings have validated the use of the lichens for the treatment of various infections in man and livestock.     

Antibacterial Activity of Jordanian Medicinal Plants

The antibacterial activity of ethanol extracts of 15 plant species used in the traditional medicine in Jordan and other Middle East countries were tested. Extracts of certain parts of these plants were tested in vitro against 14 pathogenic bacterial species and strains using the agar diffusion method. Results evaluated as the diameter of inhibition zone of bacterial growth showed that 25 mg/well of 12 plant extracts have antibacterial activity on one or more of the tested bacteria. Three plants exhibited broad spectrum antibacterial activity: Punica granatum L., Quercus infectoria Olive., and Rhus coriaria L. The most susceptible bacteria were Pseudomonas aeruginosa, Bacillus cereus and Streptococcus pyogenes (ATCC 12351), and the most resistant species were Escherichia coli (ATCC 25922 and clinical isolates), Klebsiella pneumoniae, Shigella dysentriae (ATCC 49345), and Yersinia enterocolitica (ATCC 9610). The minimum inhibitory concentrations (MIC) of active extracts ranged from 4-32 mg/ml while the minimum bactericidal concentrations (MBC) were exerted at higher doses 8-62 mg/ml.     

Characterization of phenolic content,in vitro biological activity,and pesticide loads of extracts from white grape skins from organic and conventional cultivars

Grape skin extracts of Riesling Vitis vinifera L. grapes from conventionally or organically managed cultivars were compared on the basis of their phenolic content, antioxidant capacity, antimicrobial and antimutagenic properties and pesticide loads. Promising results on their biological properties suggest that those extracts would be valuable as food preservatives. The antioxidant capacity of conventional extracts was significantly higher, according to the higher content in catechin, epicatechin and procyanidin B. Pesticide loads did not affect the antimutagenic or antimicrobial properties of the extracts. Both extracts inhibited the growth of Gram-positive foodborne pathogens such as Staphylococcus aureus, Enterococcus faecalis and Enterococcus faecium to similar extents. Possibly as a result of higher amounts of quercetin and its derivatives, higher antimicrobial effects against Listeria monocytogenes and Salmonella typhimurium were observed for the organic white grape skin extracts. Conventional or organic extracts did not show remarkable antimutagenic effects when tested against the mutagen IQ by means of the Ames test. Due to the presence of fungicides, the conidial germination of Penicillium expansum, Penicillium chrysogenum and Aspergillus niger, were inhibited by 95% by conventional GSE, while negligible effects were observed with organic grape extracts. The latter, however, showed inhibitory effects against Trichoderma viridie and Aspergillus versicolor.     

Antiproliferative constituents in plants 14. Coumarins and acridone alkaloids from Boenninghausenia japonica NAKAI

The MeOH extracts of the ground part and the root of Boenninghausenia japonica NAKAI showed inhibitory activity against tumor cell growth. Fractionation of the extracts has resulted in isolation of 1,3-dihydroxy-4-(2'-hydroxy-3'-hydroxymethyl-3',4'-epoxy-butyl)-N-methylacridone, 1,3-dihydroxy-4-[(Z)-3'-hydroxy-3'-methyl-buten-1'-yl]-N-methylacridone, 3-(1',1'-dimethylallyl)-7-hydroxy-8-methoxy-2H-1-benzopyran-2-one, casegravol, cis-casegravol, and edgeworin in addition to 9 compounds reported from B. japonica and B. albiflora. The isolates from this plant and some related compounds were tested for antiproliferative activity against human gastric adenocarcinoma (MK-1), human uterus carcinoma (HeLa), and murine melanoma (B16F10) cells.     

Assays of physical stability and antioxidant activity of a topical formulation added with different plant extracts

In the present investigation the changes on physical stability (pH, viscosity, flow index and tixotropy) of topical formulations were evaluated following inclusion of different plant extracts containing flavonoids. Also, the antioxidant effect of these plant extracts alone and after addition in the formulation was evaluated using chemiluminescence and the stable free radical 1,1-diphenyl-2-picrylhydrazyl (DPPH(.-)) assays, as well as the inhibition of lipid peroxidation. Formulation added with dl-alpha-tocopherol was used to compare the physical stability and antioxidant activity. Formulations with plant extracts showed pseudoplastic behavior with decreasing on viscosity and tixotropy. The Glycyrrhiza glabra (GG) and Ginkgo biloba (GB) extracts alone and the formulations containing these extracts showed great antioxidant and free radical scavenging activities while the other extracts studied (mixture of Glycyrrhiza glabra, Symphytum officinale L and Arctium majus root, Nelumbium speciosum and soybean) showed lower activity. The results suggest that GG and GB extracts may be used in topical formulations in order to protect skin against damage caused by free radical and reactive oxygen species.