Anticonvulsant Activity of Extracts of Diospyros Fischeri Stem Bark

Evaluation of extracts of Diospyros fischeri Gurke (Ebenaceae), which is used traditionally for the treatment of epilepsy shows that the aqueous extract of the tem bark has no effect againstpicrotoxin induced convulsions in mice. However, an 80% ethanol extract of the bark caused dose-dependent suppression of convulsions induced by 10 mg/kg body wt picrotoxin, at doses between 100–3200 mg/kg body wt. Petroleum ether, 1:1 dichloromethane:methanol, and methanol extracts also suppressed picrotoxin-induced convulsions, but had a slightly lower inhibitory effect. The petroleum ether extract was the most active, but all were less active than the ethanol extract. Unlike phenobarbitone, which at 50 mg/kg body wt completely suppressed convulsions induced by 10 mg/kg body wt picrotoxin, none of the plant extracts completely suppressed convulsions in the mice. These results support the traditional uses of D.fischeri for the treatment of epilepsy. Given the seemingly innocuous nature of the extracts more work is suggested to ascertain their clinical application.     

Investigation on Antidiarrhoeal Activity of Aristolochia Indica Linn. Root Extracts in Mice

Background

The present study aimed at investigating the effect of ethanolic extract (EtAI), and aqueous extract (AqAI) of Aristolochia indica Linn roots on castor oil-induced diarrhoea and study on small intestinal transit. Phytochemical analysis of extracts was performed as per standard procedure.

Materials and Methods

The oral toxicity study using Swiss albino mice was performed in accordance with OECD guidelines. The EtAI and AqAI extracts of Aristolochia indica Linn were studied for antidiarrhoeal property using castor oil-induced diarrhoeal model and charcoal-induced gastrointestinal motility test in Swiss albino mice.

Results

Among the tested doses of 200 and 400 mg/kg body weight, the extracts reduced the frequency and severity of diarrhoea in test animals throughout the study period. At the same doses, the extract delayed the intestinal transit of charcoal meal in test animals as compared to the control and the results were statistically significant.

Conclusion

Experimental findings showed that ethanol extract of Aristolochia indica Linn root possess significant antidiarrheal activity and may be a potent source of anti-diarrhoeal drug in future.     

Screening of Various Botanical Extracts for Antioxidant Activity Using DPPH Free Radical Method

Aiming at the exploration of herbal use by society, crude extracts of the seeds of some commonly used medicinal plants (Vitis vinifera, Tamarindus indica and Glycin max) were screened for their free radical scavenging properties using ascorbic acid as standard antioxidant. Free radical scavenging activity was evaluated using 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical. The overall antioxidant activity of grape seeds (Vitis vinifera) was the strongest, followed in descending order by soybean (Glycin max) and tamarind (Tamarindus indica). The seeds extract of Vitis vinifera, Glycin max and Tamarindus indica showed 85.61%, 83.45% and 79.26%, DPPH scavenging activity respectively.     

The Antimicrobial Activity of Liquidambar Orientalis Mill. Against Food Pathogens and Antioxidant Capacity of Leaf Extracts

Background

Medicinal plants are an important source of substances which are claimed to induce antimicrobial, antimutagenic and antioxidant effects. Many plants have been used due to their antimicrobial treatments. Antimicrobial and antioxidant activities of L. orientalis have not been reported to the present day. The aim of this work was to investigate of the antimicrobial and antioxidant potentials of different extracts from L. orientalis.

Materials and Methods

The extracts were screened for antimicrobial activity against different food pathogens. These bacteria include 4 Gram positive and 3 Gram negative bacteria and one fungi. The leaf extracts of plant were tested by disc diffusion assay. The MIC was evaluated on plant extracts as antimicrobial activity. In addition to, the plant extracts were tested against the stable DPPH (2,2-diphenyl-1-picryl-hydrazylhydrate) free-radical.

Results

The acetone, ethanol and methanol extracts of L. orientalis showed maximum inhibition zone of 12 mm against Yersinia enterocolitica, Listeria monocytogenes and Staphylococcus aureus. In addition to, the methanol extract displayed a strong antioxidant activity (trolox equivalent = 2.23 mM).

Conclusion

L. orientalis extracts have antimicrobial, and antioxidant potential. Our results support the use of this plant in traditional medicine and suggest that some of the plant extracts possess compounds with good antibacterial properties that can be used as antibacterial agents in the search for new drugs.     

Antimalarial Activity in Crude Extracts of Some Cameroonian Medicinal Plants

Fifteen crude extracts from the stem bark and seeds of four medicinal plants, viz: Entandrophragma angolense, Picralima nitida, Schumanniophyton magnificum and Thomandersia hensii were tested in vitro for their antimalarial activity against the chloroquine-resistant Plasmodium falciparum W2 strain. The results showed that the extracts of these plants possessed some antimalarial activity, the methanol extract of Picralima nitida demonstrating the highest activity in vitro. Further isolation and identification of some active compounds from these plants will justify their common use in traditional medicine for the treatment of malaria or fever in Cameroon.     

Antifungal Activity of Crude Extracts of Gladiolus Dalenii van Geel (Iridaceae)

Bulb extracts of Gladiolus dalenii reportedly used in the treatment of fungal infections in HIV/AIDS patients in the Lake Victoria region were tested for antifungal activity using the disc diffusion assay technique. Commercially used antifungal drugs, Ketaconazole and Griseofulvin (Cosmos Pharmaceuticals) were used as standards. Dichloromethane (CH₂CL₂)/Methanol (MeOH) in the ratio 1:1. Soluble extracts showed antifungal activity against Aspergillus niger. Direct bioautography on silica gel Thin Layer Chromatography (TLC) and appropriate spraying agents were used to identify the active component in the extract. The activities of both the extracts were higher than that of Griseofulvin. CH₂CL₂ soluble extract in addition showed ability to delay sporulation in A.niger. The active group of compounds in the extracts was identified as alkaloids, which offer immense potential for development of new and valuable pharmaceutical products.     

Antimicrobial Activity of Extracts from In Vivo and In Vitro Propagated Lamium Album L. Plants

The antimicrobial activity of 18 different extracts from in vivo and in vitro grown L. album L. plants was evaluated against clinical bacteria and yeasts using the well diffusion method. All the used extracts demonstrated antibacterial activity, whereas only the water extracts from leaves (in vivo) possessed antifungal activity against Candida albicans NBIMCC 72 and Candida glabrata NBIMCC 8673 (14 and 20 mm diameter of inhibition zones and MIC 10 mg/ml, respectively). The methanol and ethanol extracts obtained from the in vitro propagated plants had a broader spectrum of antibacterial activity than those from in vivo plants, while the opposite tendency was observed for the chloroform extracts. All tested flower extracts possessed antimicrobial activity. The chloroform extract from in vivo flowers demonstrated the highest activity against E. faecalis NBIMCC 3915, S. aureus NBIMCC 3703, P. hauseri NBIMCC 1339 and P. aeruginosa NBIMCC 3700 (22 mm, 13 mm, 11 mm, 23 mm zone diameter of inhibition and MIC 0.313 mg/ml, respectively). The water extracts from leaves (both in vivo and in vitro) possessed higher antibacterial activity than extract from flowers. The obtained results showed that both in vivo and in vitro propagated L. album L. could be used as a source of antibacterial substances.     

Antibacterial Activity of Extracts of Three Croton Species Collected in Mpumalanga Region in South Africa

The antibacterial activities of three Croton species were compared using bioautography and the serial microdilution methods. The methanolic extracts of all the species had low activity against Escherichia coli. The highest activity was observed with Croton megalobotrys against Enterococcus faecalis with a minimal inhibitory concentration (MIC) value of 0.02 mg/ml. Croton steenkapianus extracts were the least active of the species investigated, only managing an MIC value of 0.625 mg/ml against Pseudomonas aeruginosa. Croton megalobotrys leaf powder was serially extracted using solvents of various polarities. The lowest MIC value (0.06 mg/ml) of the serially extracted fractions was observed with acetone against Pseudomonas aeruginosa. The liquid-liquid fractions of the methanol extract of Croton megalobotrys were also tested. The lowest MIC value of 0.02 mg/ml was observed with n-hexane fraction against Enterococcus faecalis. The carbon tetrachloride fraction was further fractionated using column chromatography with silica as the immobile phase. The resulting seven fractions were tested for activity following the bioassay-guided practice, and it emerged that the first three fractions had active compounds against Staphylococcus aureus when the bioautography method was used.     

Antimicrobial Activity of Carpolobia Lutea Extracts and Fractions

Carpolobia lutea (G. Don) (Polygalaceae) is a tropical medicinal plant putative in traditional medicines against gonorrhea, gingivitis, infertility, antiulcer and malaria. The present study evaluated the antimicrobial, antifungal and antihelicobacter effects of extracts C. lutea leaf, stem and root. The extracts were examined using the disc-diffusion and Microplates of 96 wells containing Muller-Hinton methods against some bacterial strains: Eschericia coli (ATCC 25922), E. coli (ATCC10418), Pseudomonas aeruginosa (ATCC 27853), Staphylococcus aureus (ATCC 25923), Staphyllococus aureus (ATCC 6571), Enterococcus faecalis (ATCC 29212) and Bacillus subtilis (NCTC 8853) and four clinical isolates: one fungi (Candida albican) and three bacteria (Salmonella, Sheigella and staphylococcus aureus). The Gram-positive bacteria: Staphylococcus aureus (ATCC 25923), Enterococcus faecalis (ATCC 29212), Bacillus subtilis (ATCC 19659) and the Gram-negative bacteria: Escherichia coli (ATCC 25922), Pseudomonas aeruginosa (ATCC 27853), Cândida albicans (ATCC 18804) and Helicobacter pylori (ATCC 43504). Some of these extracts were found to be active against some tested strains but activity against H. pylori was >1000mg/ml and good fungistatic activity against C. albican. The MIC against C. albican is in the order n-HF > CHF > ETF= EAF.The order of potency of fraction was the ethanol root > n-HF leaf > ethanol fraction stem > chloroform fraction leaf = ethyl acetate fraction leaf. Polyphenols were demonstrated in ethanol fraction, ethyl acetate fraction, crude ethyl acetate extract and ethanol extract, respectively. These polyphenols isolated may partly explain and support the use of C. lutea for the treatment of infectious diseases in traditional Ibibio medicine of Nigeria.     

Antibacterial Activity of Tabernaemontana Stapfiana Britten (Apocynaceae) Extracts

Antibacterial and phytochemical screening of methanolic, sequential extracts (hexane, dichloromethane, ethyl acetate and methanol) and alkaloid rich fractions of Tabernaemontana stapfiana Britten was carried out. The phytochemical screening showed the presence of alkaloids, flavonoids, coumarins, tannins and saponins that have been associated with antimicrobial activity. The stem and root bark methanolic extracts showed good activity against the bacterial strains used including the multiple drug resistant Staphylococcus aureus strain with minimum inhibitory concentrations ranging from 15.6 to 500 µg/ml and minimum bactericidal concentrations ranging from 31.25 to 500 µg/ml. The sequential extracts of the root and stem bark had high antimicrobial activity with minimum inhibitory concentrations (MICs) ranging between 3.9 and 250 µg/ml and minimum bactericidal concentrations (MBCs) ranging between 7.8 and 500 µg/ml against the tested microorganisms. The dichloromethane extract of the alkaloid rich fractions however exhibited reduced antibacterial activities as compared to methanol and sequential extracts but the dichloromethane:methanol (4:1) mixture showed high activity with MICs ranging between 15.6 and 250 µg/ml. These antibacterial efficacy studies suggest that Tabernaemontana stapfiana Britten could be a source of antibacterial agents.     

Phytotherapeutic Activity of Euphorbia Cyparissias Extracts on Ixodidae (Acari) Female Ticks

Background

Given its numerous biologically active components, Euphorbiaceae has been found to be a large plant family and polyvalent with quite interesting therapeutic activity that can be studied.

Materials and Methods

The ixodicidal activity of Euphorbia cyparissias extracts was studied in vitro and in vivo. Tested concentrations were 10, 5, 2, 1, 0.5 and 0.25%.

Results

For the in vitro study, conducted on field-collected female specimens of Dermacentor marginatus and Haemaphysalis punctata, the efficacy results showed that the ticks died after exposure in the case of 10, 5, and 2% tincture concentrations. The effects appeared after 30 minutes and became more visible 120 minutes after each exposure. The statistical differences regarding the used concentrations were found to be: F = 6.51, df = 5, P < 0.001. The in vivo study of the efficacy of E. cyparissias concentrations was performed on 35 naturally infested sheep and on 30 bovines parasitized with Ixodes ricinus, sprayed with tincture and glycerinate dilutions (bovines) on days 0 and 7. The results revealed detrimental effects on the survivability of female ticks, the most prominent being the reduction of their movement capacity. In sheep in vivo efficiency observed within 24 hrs varied, between 1 and 23% for D. marginatus and between 7 and 27% for H. punctata and respectively between 2 and 53% after 24 hrs, for I. ricinus, comparable effects being also found 72 hrs after the second administration of Euphorbia extracts.

Conclusion

Extracts from E. cyparissias may be used, with results, as an ecologic alternative tick control management method, being a cheap solution, with a sizeable role in reducing the use of synthetic and/or other harming and resistance source ixodicidal conditionings.     

Antimicrobial Activity of Extracts and Topical Products of the Stem Bark of Spathodea Campanulata for Wound Healing

The antibacterial activity of the aqueous, ethanol, methanol and petroleum ether Soxhlet extracts of sundried stem bark of Spathodea campanulata P. Beauv. (Bignoniaceae) was investigated by testing the extracts against B. subtilis, E. coli, P. aeruginosa and S. aureus. The minimum inhibitory concentration (MIC) of the methanol extract was determined against the four bacteria strains and C. albicans using the broth dilution method. Four topical products were prepared by incorporating the methanol extract of S. campanulata (20 % w/w) into aqueous cream, soft paraffin, emulsifying ointment and simple ointment bases and evaluated for their in vitro antimicrobial efficacy. The effect of storage time on the activity of the methanol extract of S. campanulata and S. campanulata extract incorporated in aqueous cream base was also investigated. The methanol and ethanol extracts showed good activity while the aqueous and petroleum ether extracts exhibited little activity. The methanol extract showed the best antibacterial activity. The MIC of the methanol extract of S. campanulata was: C. albicans (45 – 50 mg/ml), B. subtilis and E. coli (50 – 55 mg/ml), P. aeruginosa (60 – 65 mg/ml), S. aureus (145 – 150 mg/ml). Antimicrobial activity of S. campanulata in the topical bases was in the order: aqueous cream > emulsifying ointment > simple ointment > white soft paraffin. Antimicrobial activity of S. campanulata in aqueous cream decreased (p < 0.05) upon storage at room temperature for 6-months. The antifungal activity of the methanol extract of S. campanulata was reduced (p < 0.05) upon storage while antibacterial activity was largely unaffected.     

In Vitro Antimicrobial Activity of Crude Extracts from Plants Bryophyllum Pinnatum and Kalanchoe Crenata

Extracts from the leaves of Bryophyllum pinnatum and Kalanchoe crenata were screened for their antimicrobial activities. Solvents used included water, methanol, and local solvents such as palmwine, local gin (Seaman''s Schnapps 40% alcoholic drink,) and “omi ekan-ogi” (Sour water from 3 days fermented milled maize). Leaves were dried and powdered before being soaked in solvents for 3 days. Another traditional method of extraction by squeezing raw juice from the leaves was also employed. All extracts were lyophilized. These extracts were tested against some Gram-negative organisms (Escherichia coli ATCC 25922, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Shigella flexneri, Salmonella paratyphi, Citrobacter spp); Gram-positive organisms Staphylococcus aureus ATCC 25213, Staphylococcus aureus, Enterococcus faecalis, Bacillus subtilis) and a fungus (Candida albicans). Agar well diffusion and broth dilution methods were used to determine the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) at concentrations of 512mg/ml to 4mg/ml. All the organisms except Candida albicans were susceptible to the extracts obtained from the traditional method. The squeezed-leaf juice of Kalanchoe crenata was the most active one with MIC of 8 mg/ml against Pseudomonas aeruginosa, Klebsiella pneumoniae and Bacillus subtilis, 32 mg/ml against Shigella flexneri, 64 mg/ml against Escherichia coli and 128 mg/ml against the control strain Staphylococcus aureus while its MBC is 256 mg/ml against these organisms except Bacillus subtilis and Klebsiella pneumoniae. The Gram-positive organisms were more sensitive to the methanol and local gin-extract of Bryophyllum pinnatum. Extracts from other solvents showed moderate to weak activity.     

Antimicrobial Activity of Methanolic Extracts of Sambucus Ebulus and Urtica Dioica Against Clinical Isolates of Methicillin Resistant Staphylococcus Aureus

Background

Increase in the emergence of drug -resistant pathogens led to the development of natural antimicrobials. In this study the antimicrobial effect of methanolic extracts of Sambucus ebulus and Urtica dioica on 16 skin and wound infections isolates of methicillin resistant S. aureus have been studied.

Material and Methods

Solvent extraction procedure was done using soxhlet apparatus for extracting antimicrobial agents from freeze dried plants. Antibacterial activity was measured using agar well diffusion method.

Results

The MIC of Sambucus ebulus and Urtica dioica extracts against the standard strain of S. aureus ATCC 6538 were determined using the micro dilution method at 15 mg and 20 mg respectively. All the test bacteria were found sensitive to the Sambucus ebulus extract and only one isolate was resistant to Urtica dioica extract.

Conclusion

Extracts of Sambucus ebulus and Urtica dioica possess antibacterial potency against MRSA isolates and may be used as a natural antiseptics and antimicrobial agents in medicine.     

In Vitro Evaluation of Antiplasmodial Activity of Extracts of Acanthospermum Hispidum DC (Asteraceae) and Ficus Thonningii Blume (Moraceae), Two Plants Used in Traditional Medicine in the Republic of Congo

The aim of this study was to evaluate extracts from two medicinal plants, Acanthospermum hispidum and Ficus thonningii, used in traditional medicine in Congo Brazzaville, for in vitro antiplasmodial activities against two laboratory strains of Plasmodium falciparum: the chloroquine sensitive 3D7 and the chloroquine resistant Dd2. ELISA HRP2 assay was used to evaluate the in vitro inhibitory activity of the extracts alone or in combination with chloroquine. Cytotoxicity was assessed on human HeLa cell line and reflected by the selectivity index. Methanolic extract of Acanthospermum hispidum exhibited a strong and a moderate inhibitory activity on the growth of Dd2 and 3D7 at 2.8 µg/ml and 9.2 µg/ml concentrations respectively with a selectivity index >10. The combination of the most active extract (methanolic extract of Acanthospermum hispidum) with chloroquine showed a synergistic interaction on both strains. The good selectivity index of Acanthospermum hispidum on HeLa cells reflects the safety of this plant. Extracts from Ficus thonningii did not show any promising antiplasmodial activity on both 3D7 and Dd2. Except the methanolic extract which exhibited a slight antiplasmodial activity with inhibitory concentration and selectivity index corresponding to 9.61 µg/ml and 11.16 respectively. Methanolic extract of Acanthospermum hispidum exhibited moderate to high inhibitory activity on 3D7 and Dd2 laboratory strains and a synergistic antimalarial effect when combined with chloroquine. Ficus thonningii seems to have no antimalarial activity. Phytochemical analysis, in vivo investigations using animal models and later clinical trials in collaboration with traditional practitioners are necessary to clarify the potential antimalarial activity of both plants.     

Lipid Fraction Constituents and Evaluation of Anti-Anaphylactic Activity of Prunus Mahaleb L. Kernels

The lipid fraction constituents as well as evaluation of anti-anaphylactic activity of Prunus mahaleb L. Kernels were studied. Prunus mahaleb L. kernels were obtained from the local market in Cairo, Egypt. Investigation of the fatty acids revealed that oleic and linoleic acids are the major constituents. 12 compounds were identified from the hydrocarbon fraction. The sterol fraction comprises of cholesterol, stigmasterol, β-sitosterol and campesterol. The pharmacotoxicity studies were carried out on total and defatted ethanolic extracts as well as the oil fraction. The oil fraction proved to be extremely safe and free from any acute lethal toxicity in intraperitoneal (i.p.) and oral doses up to 100 ml/kg. Invivo assessment of prophylactic efficacy was afforded by 7 days course of daily medication schedule of sensitized adult male guinea pigs against ovalbumin bronchospasm. The prophylactic anti-inflammatory activity of the total ethanolic extract was higher than that of the defatted ethanolic extract. In addition, the lipid fraction of Prunus mahaleb L. kernels evoked complete anti-inflammatory efficacy among the survival animals receiving low and medium doses.     

Cytotoxicity,Phytochemical Analysis and Antioxidant Activity of Crude Extracts from Rhizomes of Elephantorrhiza Elephantina and Pentanisia Prunelloides

Background

Elephantorrhiza elephantina (Ee) and Pentanisia prunelloides (Pp) are two medicinal plants which are widely used to remedy various ailments including diarrhoea, dysentery, inflammation, fever, rheumatism, heartburn, tuberculosis, haemorrhoids, skin diseases, perforated peptic ulcers and sore joints in southern Africa (South Africa, Swaziland, Botswana and Zimbabwe). The following study was conducted to explore the in vitro cytotoxicity, antioxidant properties and phytochemical profile of the two medicinal plants.

Materials and Methods

The cytotoxicity of the aqueous and methanol extracts and fractions of both species was studied using the brine shrimp lethality tests (BST) for the first time.

Results

The results demonstrated that the lethality (LC₅₀) for crude extracts for both plants ranged between 1.8 and 5.8 ppm and was relatively greater than that for the methanol, ethyl acetate and chloroform fractions of the extracts which ranged between 2.1 ppm and 27 ppm. This suggested that crude extracts were more potent than their respective fractions, further explaining that the different fractions of phytochemicals in these plant species work jointly (in synergy) to exert their therapeutic efficacy. Both aqueous and methanol extracts of the two medicinal plants demonstrated a high degree of antioxidant capacity against the DPPH radical with the Duh and Yen inhibition percentage ranging between 4.5% and 72%. Phytochemical studies of the rhizome extracts showed that the major compounds present include flavonoids, tannins, anthocyanidins, anthraquinones, triterpenoids (oleanolic acid), the steroidal saponin Diosgenin, the sugars, rhamnose, glucuronic acid, Arabinose and hexoses.

Conclusion

This is the first report of the detection and isolation of diosgenin and oleanolic acid from the rhizome extracts of Ee and Pp. All structures were determined using spectroscopic/spectrometric techniques (1H NMR and 13C and LC-ESI-MS) and by comparison with literature data.     

Antibacterial and Anti-Biofilm Activity of Flavonoids and Triterpenes Isolated from the Extracts of Ficus Sansibarica Warb. Subsp. Sansibarica (Moraceae) Extracts

Background

Ficus species are used in African traditional medicine in the treatment of a wide variety of ailments and diseases such as convulsive disorder, wound healing, gonorrhea, tuberculosis, diabetes, diarrhoeal infections, dysentery, malaria and HIV. The aim of this study was to isolate the phytochemical constituents in the plant and test them for their antibacterial activity.

Materials and methods

The fruits, leaves and stem bark were extracted with organic solvents and the compounds in the extracts separated and purified by column chromatography before being identified by NMR spectroscopy and by comparison of the NMR data against values reported in the literature. The antibacterial activity of the pure compounds and extracts were tested using the disk diffusion method.

Results

Three triterpenes and three flavonoids: lupeol acetate (1); cycloart-23-ene-3,25-diol (2); β-sitosterol (3); 5,7,4′-trihydroxyflavan-3-ol (4); epicatechin (5); and isovitexin (6) were isolated in this study. Antimicrobial activity was observed at 8 mg mL⁻¹ for Staphylococcus aureus ATCC 29213 with four of the six isolated compounds, with no activity being observed at 1 – 4 mg mL⁻¹ against Escherichia coli ATCC 25922, E. coli ATCC 35218 and S. aureus ATCC 43300. Epicatechin (5) was found to decrease adhesion of E. coli ATCC 25922 and S. aureus ATCC 29213. Decreased adhesion of S. aureus ATCC 29213 was also observed with 5,7,4′-trihydroxyflavan-3-ol (4) and isovitexin (6).

Conclusions

The results of this study provide baseline information on F. sansibarica''s potential validity in the treatment of infections associated with Gram-positive microorganisms.     

Antimicrobial Activity of Various Extracts of Ocimum Basilicum L. and Observation of the Inhibition Effect on Bacterial Cells by Use of Scanning Electron Microscopy

The antimicrobial activities of chloroform, acetone and two different concentrations of methanol extracts of Ocimum basilicum L. were studied. These extracts were tested in vitro against 10 bacteria and 4 yeasts strains by the disc diffusion method. The results indicated that the methanol extracts of O. basilucum exhibited the antimicrobial activity against tested microorganisms. While the chloroform and acetone extracts had no effect, the methanol extracts showed inhibition zones against strains of Pseudomonas aeruginosa, Shigella sp., Listeria monocytogenes, Staphylococcus aureus and two different strains of Escherichia coli. The cells of microorganisms, which were treated and untreated with plant extracts, were observed by using the scanning electron microscope. It was observed that the treated cells were damaged.