Antibacterial Activity Of Aqueous Extracts Research Articles

Bidens sulphurea and Tanacetum vulgare L. extracts against Staphylococcus spp. mecA positive in pregnant women

The present study aimed to evaluate the antibacterial activity of aqueous extracts of Bidens sulphurea and Tanacetum vulgare L. against Staphylococcus spp. methicillin-resistant (mecA) isolates from the vaginal microbiota of pregnant women. Fifteen isolates of Staphylococcus spp. with the presence of the mecA gene, from the vaginal swabs of pregnant women, aged between 16 and 38 years, who underwent microbiological examination during the first trimester of pregnancy. The aqueous extracts of B. sulphurea and Tanacetum vulgare L. were obtained by infusion, as recommended by popular use, and then, the chemical identification of the extracts was performed by gas chromatography. The antibacterial activity of plant extracts was performed by the method of microdilution in broth. B. sulphurea extract had as major compounds: custonolide (8.06%), Isohumulene (6.19%), artemetin (21,13%), β-sitosterol (28.68%), phytol (7.36%) e 7,8-epoxylanostan-11-ol, 3-acetoxy- (7.09%). T. vulgare extract presented as the majority artemetin (13.38%), verrucarol (13.27%) and phytol (11.93%), ergosterol (5.43%), ethyl iso-allocholate (6.95%), 7,8-epoxylanostan-11-ol, 3-acetoxy- (14,46%), lycopene, 1,1',2,2'-tetrahydro-1,1'-dimethoxy-, all-trans (7.09%) e 9,19-cyclochloestene-3,7-diol, 4,14-dimethyl-, 3-acetate (8.58%). The isolates tested against aqueous extracts of B. sulphurea and T. vulgare L., obtained minimum inhibitory concentrations (MIC) between 1.17mg/mL and 37.5mg/mL, minimum bactericidal concentrations (MBC) of B. sulphurea varied between 75mg/mL and 150mg/mL, on the other hand, T. vulgare L. MBC had lower values ranging from 9.37mg/mL to 150mg/mL. It was confirmed the bactericidal and bacteriostatic activity of the tested extracts against isolates that have the mecA resistance gene, and it is possible to attest that these extracts are a therapeutic alternative.

Assessment of the phenolic profile and biological activities of aqueous date seed extracts: A comparative analysis

Date palm fruit (Phoenix dactylifera L.) is a well-known fruit that has become increasingly popular among consumers due to its pleasant flavor, nutrient-dense content, and nutraceutical characteristics. Date seeds are the main by-product of date fruit consumption and processing. Date seeds are usually incorporated in animal feed; however, their application in human contexts, such as food products, remains minimal. Nonetheless, they contain significant amounts of bioactive phenolic compounds, primarily flavonoids, which possess potential health benefits. The current study investigated and compared the phenolic profile, antioxidant, and antibacterial activities of aqueous extracts of nine different date seeds varieties. The phenolic profile, analyzed using high-performance liquid chromatography (HPLC-DAD-ESI-MS), showed that total phenolic compounds ranged from 1.05 to 1.24 mg/g in Reziz and Naghal varieties, respectively, with flavan-3-ols predominating in all varieties. Results of the ABTS and DPPH assays revealed that the antioxidant activities against free radicals were directly correlated with the overall phenolic content, particularly for caffeic acid. Indeed, all date seeds possessed antibacterial capabilities, with a stronger effect observed on Listeria monocytogenes than Escherichia coli. Additionally, date seeds demonstrated a promising source of oil rich in oleic and lauric acids, both of which are considered beneficial for health. According to our findings, date seeds are a significant source of bioactive compounds, which renders them ideal candidates for potential inclusion in human diets as food additives and nutraceuticals.

In vitro antioxidant and antibacterial activities of aqueous extract of microalgae strain MRB-1, MRB-2, and MRB-3

Abstract The awareness growth of human health encourages market demand of functional food. Microalgae are promoted as natural resources for functional food, food additives and food preservatives, considering their metabolites and nutrient-rich components with diverse pharmacological activities. This study aims to evaluate the phytochemicals, antioxidant, and antibacterial activities of aqueous extracts of microalgae strain MRB-1, MRB-2, and MRB-3. The morphological surface of microalgae cells was analyzed using Scanning Electron Microscopy (SEM). The metabolites of the extract were conducted using Liquid Chromatography-High Resolution Mass Spectroscopy (LC-HRMS) with positive and negative ion modes. In addition, the antioxidant activity was evaluated using a 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay and the antibacterial activity was assessed using the agar disk-diffusion method against gram-positive bacteria (Staphylococcus aureus ATCC 25923) and gram-negative bacteria (Escherichia coli ATCC 8739). The total phenolic contents (TPC) of the extract was determined using the Folin-Ciocalteu assay. The result revealed that the aqueous extract of microalgae strain MRB-1 had the highest scavenging activity toward DPPH radicals with a value of 24.33±1.44% at 0.8 mg/mL. This data was in accordance with the TPC of the extract, whereas the highest TPC was also obtained from strain MRB-1 extract (17.73±0.64 mg GAE/g extract). Meanwhile, the MRB-2 extract had the highest inhibition activity against S. aureus, with a value of 11.78±2.06 mm at 18 mg/mL. The results of this study indicated that microalgae from the peatlands potentially benefit to human health as a natural antioxidant and antibacterial source.

The Antibacterial Activity of Aqueous Extracts of Coriander & Mustard.on Some Bacterial Isolates

This study was designed to fovestigate the actjvity of herbal decoctions on different bacterial isolates. The antibacterial activity of herbal extracts was evaluated against Staphylococcus aureus, Streptococcus pneumoniae, E. coli, Klebsiella pneumoniae and Pseudomonas aeruginosa. Decoctions of Coriander· (Cofianedum Sativum) & Mustard (Brassica Nigra) were prepared according to tractitjonal herbal recipes. Simple disk - diffusion method was employed over all the decoctions exhibited a positive effect on the bacteria by decreasing and inhibiting the bacterial growt11.

Evaluation of Antibacterial activity of aqueous extract of Cucumis melo

Plant-based phytochemicals are promising antibiotics for treating microbial illnesses in humans. The purpose of the current study is to assess the antibacterial properties of an aqueous Cucumis melo extract against Bacillus subtilis and Escherichia coli. The Agar well diffusion method is initially used to assess the antibacterial activity of the fruit's aqueous extract against the gram’s positive B. subtilis and the gram’s negative organism E. coli. Results reveal that, in comparison to the control, the Cucumis melo aqueous fruit extract at two dose levels of 200 µg/ml and 400µg/ml significantly increases the zone of inhibition of microorganisms. Additionally, a very large zone of inhibition was seen at 400µg/ml dosage. The difference between the mean values of 200 and 400µg/ml was also encouraging. The aqueous extract exhibits a considerable dose, in conclusion.

Antibacterial activity of garlic, cinnamon and chitosan against food related pathogens

Antibacterial activity of aqueous extracts and aqueous infusions of garlic, cinnamon and chitosan was investigated on food pathogens, , and . Natural antibacterial substances can be used to inhibit such pathogens and also to increase shelf life and safety of food products. All spices and herbs under study exhibited strong antibacterial activity against food related bacteria. Results suggested that among the spices investigated garlic had excellent antibacterial activity followed by cinnamon and chitosan. This indicates practical importance of these natural substances in increasing shelf life and decreasing the risk of contamination of food without any undesirable side effects which are commonly observed with the use of chemical preservatives.

PHYTOCHEMICAL SCREENING AND ANTIMICROBIAL ANALYSIS OF AQUEOUS EXTRACTS OF WILD MANGO VARIETIES

Phytochemical screening and antibacterial activity of aqueous extracts of bark and leaf of eighteen mango varieties growing in the village Hanavadi, Malavalli taluk, Mandya district, Karnataka state were conducted. They showed the presence of alkaloids, steroids, flavonoids, tannins, cardiac glycosides, saponnins, resins, carbohydrates and proteins. Antibacterial activity tested against six human pathogens- Escherichia coli, Enterobacter aerogenes, Staphylococcus aureus, Streptococcus mutans, Pseudomonas aeruginosa and Bacillus subtilis, by disc diffusion method showed significant inhibition zone against pathogens compared to control. These results disclose the inhibiting property of leaf and bark of wild varieties of mangoes against potential pathogens and thus can be subjected to further investigations for their applications in human phytomedicines.

IN VITRO ANTIBACTERIAL ACTIVITY OF AQUEOUS LEAF EXTRACTS OF CYMBOPOGON CITRATES AGAINST SELECTED BACTERIAL STRAINS

The antibacterial activity of aqueous extract of Cymbopogon citratus leaf were assessed against some selected bacterial isolates including Escherichia coli ATCC 29214, Salmonella enterica Typhi ATCC14028, Bacillus cereus ATCC 14579, Proteus vulgaris ATCC15315 Shigella flexneri ATCC 120233, Listeria monocytogenes Scott A, Listeria monocytogenes ATCC7644, Staphylococcus aureus ATCC 25823, Staphylococcus aureus ATCC 25923 and Staphylococcus aureus ATCC 29213 in vitro at different concentrations. Results obtained showed that the aqueous extract of Cymbopogon citratus leaf had antibacterial activities against test bacteria. The Minimum Inhibitory Concentration (MIC) of the aqueous extract of C. citratus leaf was observed to be 500mg/ml against Listeria monocytogenes Scott A, Staphylococcus aureus ATCC 25823, Salmonella thyphimirium ATCC 14028, Proteus vulgaris ATCC 15315 and S. aureus ATCC 25923 while it was 750mg/ml against L. monocytogenes ATCC 7644, Bacillus cereus ATCC 14579 and Shigella flexneri ATCC 120233. The antibacterial efficacy of the leaf extract of C. citratus can be ascribed to the pytochemicals in the extract; hence, C. citratus may be useful in treating infections caused by these bacteria.

NATURAL DYES FROM CONIFEROUS PLANT DEBARKING WASTE

The need to reduce greenhouse gas emissions into the atmosphere, decarbonization of industrial production makes it urgent to improve many technological schemes, including schemes for complex processing of plant resources. The authors of the article consider the possibility of recycling multi-tonnage waste bark of Siberian coniferous plants to obtain a marketable product – a natural dye for the textile industry. The study showed that the complex of coloring substances of the bark of Siberian fir, spruce and larch is mainly represented by flavonoid compounds, primarily quercetin, dihydroquercetin, kaempferol and naringin. With the presence of this class of organic compounds, the authors of the article associate the antibacterial activity of aqueous extracts from the waste of the debarking of the studied plants, as well as textile materials dyed by them. It was found that the optimal mode of extraction of a complex of coloring substances from the studied biomass is extraction with water at a temperature of 95-100 C for 120-180 minutes at a hydromodule of 1:50. The coloring of textile fibers of various natures with aqueous extracts of the bark of fir, spruce or Siberian larch gives them a rich beige-orange range of colors. High strength of coloring is recorded in the case of polyamide and mixed polyester fibers, colored with a natural dye from the bark of coniferous plants. The color strength of cotton fibers was assessed as satisfactory, and polyester fibers as insufficient. This circumstance allowed us to draw a conclusion about the expediency of coloring polyamide, cotton and mixed fibers with a natural dye from the waste of debarking coniferous plants, and the futility of such coloring of polyester textile materials.

Phytochemical Screening and in vitro Antibacterial Activity of Aqueous Extracts of Phyllanthus muellerianus (Kuntze) Exell from Kasaï Oriental (DRC) on a Few Bacterial Strains

Aims: To carry out a preliminary phytochemical study and to evaluate in vitro the antibacterial activities of aqueous extracts of different parts of P. muellerianus, a plant widely used traditionally in Kasai Oriental to treat various pathologies including several bacteriosis.
 Study Design: Based on the results of an ethnobotanical survey in Kasaï Oriental, P. muellerianus was selected because of the diversity of recipes involving it, its frequency of citation, its level of preference as well as the diversity of diseases treated and the plebiscite of its effectiveness by traditional healers. To contribute to the enhancement of this plant traditionally used against various bacteriosis and to confirm its therapeutic power, the phytochemical screening of its different parts was carried out and the antibacterial potential of various aqueous extracts was evaluated in vitro.
 Place and duration of Study: Analyzes were carried out from February to September 2017 at the Physico-chemical and microbiological analysis laboratories of the Congolese Office of Control of Mbujimayi as well as at the Biology and Chemistry laboratories of ISP Mbujimayi.
 Methodology: Fourteen bioactive chemical groups were investigated in the leaves, stem barks and those of the roots of this plant according to standard methods of characterization based on precipitation, coloring and moss reactions. In vitro, the diameters of the zones of inhibition as well as the MIC and MBC of each of different aqueous extracts were determined against 20 bacterial strains of 13 species responsible for bacterial diseases in humans.
 Results: The phytochemical screening revealed that all three parts of P. muellerianus contain abundant and diverse bioactive chemical groups. This species contains alkaloids, quinones, steroids, terpenes, saponins, tannins, and flavonoids. In vitro bacteria-aqueous extract interaction tests demonstrated that all three aqueous extracts have inhibitory activity on several of the 20 bacterial strains tested. According to MIC and MBC, inhibitory performance varies depending on the germs and extracts. The sensitivity of different bacterial strains to an extract is also variable; each extract having its spectrum of inhibitory actions.
 Conclusion: The results confirm the therapeutic potential of P. muellerianus by the presence of several bioactive substances in all its parts and by the diversity of the inhibitory activity of different extracts on several of a few bacterial strains submitted to the tests.

In vitro antibacterial activity of extracts of Dalbergia sissoo and Aegle marmelos against Enterotoxigenic Escherichia coli from calves

Neonatal calf diarrhoea (NCD) is the most common cause of morbidity and mortality in pre-weaned dairy calves, causing huge economic and productivity losses to dairy industry worldwide. Enterotoxigenic E. coli (ETEC) is one of the important causes of neonatal diarrhoea and high mortality in very young calves. Shisham (Dalbergia sissoo) leaves and Bael (Aegle marmelous) unripe fruit have been used in diarrhoea and dysentery with very good results. Hence the present study was conducted to evaluate the in vitro antibacterial activity of the aqueous and methanolic extract of Dalbergia sissoo and Aegle marmelos against 16 E. coli isolated from colibacillosis affected diarrhoeic calves in Bikaner district of Rajasthan. The average zones of inhibitions of aqueous extract of Aegle marmelos and methanolic extract of Dalbergia sissoo against E. coli were 23.75±0.34 mm, 18.75±0.32 mm, 16.5±0.24 mm, 11.58 ±0.14 mm and 7.88±0.24 mm at concentrations of 1000 mg/ml, 500 mg/ml, 250 mg/ml 125 mg/ml and 62.5 mg/ml, respectively. The average zones of inhibition of aqueous extract of Dalbergia sissoo and methanolic extract of Aegle marmelos against E. coli were 24.75±0.20 mm, 19.87±0.34 mm, 17.25±0.24mm, 12.86±0.13 mm and 8.50±0.14 mm at concentrations of 1000 mg/ml, 500 mg/ml, 250 mg/ml 125 mg/ml and 62.5 mg/ml, respectively. The maximum zone of inhibition was reported by aqueous extract of Dalbergia sissoo and methanolic extract of Aegle marmelos (>24 mm of diameter) at concentration of 1000 mg/ml. Based on average zone of inhibition, the in vitro antibacterial activity of aqueous extract of Dalbergia sissoo and methanolic extract of Aegle marmelos was found to be more against E. coli as compared to aqueous extract of Aegle marmelos and methanolic extract of Dalbergia sissoo at varying concentrations. In conclusion, both combination of aqueous and methanolic extract of Dalbergia sissoo and Aegle marmelos showed in vitro antibacterial properties against E. coli.

Evaluate the efficacy of Antimicrobial activity of aqueous extract of Nigella sativa seeds powder on Staphylococcus aureus

In Siddha medicine system has been classified into Aga marunthu (Internal) and Pura marunthu (External) having 32 forms of medicines in each. The external remedies are very useful for topical ulcers, skin diseases like eczema, psoriasis bacterial and fungal infections. The purpose this study was Evaluate the efficacy of Antibacterial activity of aqueous extract of Nigella sativa seeds powder against Staphylococcus aureus by used disk diffusion method. The result has been evaluated as the diameter of the zone of inhibition of microbial growth showed that the different concentration (100%, 50%, 25%) of Nigella sativa seed powder’s aqueous extract more effective against Staphylococcus aureus. Mean value of the hot extract 100%, 50%, 25% respectively 12.19±1.91mm, 7.63±2.32 mm and 3.78±1.73mm and the mean value of Cold extract were 9.45±1.32mm, 4.21±0.92mm and 2.71±.64mm. Standard maintained 18mm of zone of inhibition .Among the hot and cold extract, 100% of hot extract was showed more significant affect against Staphylococcus aureus which was 12.19mm. Finally this study was concluded that the Nigella seeds powder can be used as an antibacterial agent.
 
 

PHYTOCHEMICAL SCREENING AND ANTIBACTERIAL ACTIVITY OF DIOSCOREA BULBIFERA L. FRUITS

Dioscorea bulbifera (Pita aalu) is a medicinal plant belongs to famility Dioscoreaceae, used to cure various diseases like malaria, diarrhoea, diabetes, dysentery, cancer, piles and skin infections. We designed the present study to analyse phytochemical and antibacterial activity of D. bulbifera fruit so as to conform its edible property. For this we followed phytochemical screening of the fruit extracts and found that it is consist of tannin, saponin, phenols, steroids, terpenoids and some carbohydrates in high concentration. The antibacterial activity of aqueous extract of the fruit against Streptococcus mutans pathogen was determined by using agar well diffusion, disc diffusion and broth dilution assay. From the results it was confirmed that the aqueous extract of the fruits of D. bulbifera showed high inhibition zone at 100µg/ml is 19 mm in agar well diffusion, 14 mm in disc diffusion assay. The minimum inhibitory concentratiom (MIC) of extract of D. bulbifera arranged in respect to the parts from 100 µg/ml, 200 µg/ml, 300 µg/ml, 400 µg/ml, 500µg/ml and inoculums control showed visible growth due to no antimicrobial agents, whereas the broth control showed no growth due to absence of bacteria. Presence of primary and secondary metabolites indicates the nutraceutical value of D. bulbifera fruits. So the fruits of D. bulbifera can be used as a tool against antimicrobial resistance (AMR).

Antibiotic resistance profile of gram-negative bacteria isolated from dog nasal swab samples, and antibacterial and antioxidant activities of aqueous extracts of Alpinia purpurta (Vieill.) K. Schum (Zingiberaceae)

The indiscriminate use of antibiotics in veterinary medicine and their negligent use among dog owners have contributed to the rise of antibiotic resistance in microorganisms found in pets. In addition, the search for medicinal plants with antibacterial properties has made the evaluation of aqueous extracts of Alpinia purpurata (Vieill.) K. Schum an important issue. Thus, the aim of this work was to determine the antibiotic resistance profile of gram-negative bacteria isolated from nasal swab samples of dogs and assess the antibacterial activity of the aqueous extracts of leaves and rhizomes of A. purpurata. The bacteria identified were tested using the agar disc diffusion assay for the evaluation of antibiotic resistance. A total of 16 isolates were obtained from the 19 samples collected, with a high prevalence of Escherichia coli (n=5). There was a high rate of resistance to ?-lactams, where the highest percentage was seen for amoxicillin (72.5%). Aqueous leaf extracts had high levels of total phenolic compounds (637.47 µg GAE mg-1), differing significantly (p < 0.05) from aqueous rhizome extracts (228.64 µg GAE mg-1). There was no significant difference in EC50 of DPPH values between the aqueous extracts; however, the antioxidant capacity of rhizome extracts had higher values than leaf extracts. The minimum inhibitory concentration (MIC) of leaves and rhizomes for the evaluated bacteria ranged from 9000 to 32,000 µg mL-1. For the minimum bactericidal concentration (MBC), most bacteria showed an MBC over 38,400 µg mL-1 for the rhizome. In conclusion, the bacteria isolated from dog nasal swabs showed a high resistance profile for the antibiotics of the penicillin class. Additionally, the results from the analysis of the aqueous extracts of rhizomes and leaves of A. purpurata showed an antimicrobial effect possibly associated with a high content of total phenolic compounds; these results can create a scope for using these extracts together with conventional antibiotics to control the emergence of antibiotic resistance among microbial species.

Antibacterial Activity of Common Spices Extracts on Bacterial Isolates found in Kachhila, a Newari Cuisine

Objectives: The objective of this study was to determine the antibacterial property of aqueous extracts of common spices used in the preparation of Kachhila such as garlic, ginger, and turmeric.
 Methods: After washing and cleaning separately, aqueous extracts were extracted from each spice by crushed with mortar and pestle. Antibacterial activity of aqueous extracts of each spice was evaluated by using agar well diffusion assay and paper disc diffusion assay against test bacteria isolated from buff meat used in Kachhila preparation. 
 Results: Minimum inhibition concentration value of each spice was evaluated against all bacterial isolates. Total bacterial count (CFU/g) of prepared Kachhila was determined in each 30 mins interval up to 150 mins to reveal antibacterial activities of spices used in Kachhila. The antibacterial effect of aqueous extract of garlic extract was found to be the stronger in comparison, followed by turmeric and ginger against test bacterial isolates. The MIC of individual spice extract was found to be 125 to 4000 μl/ml against all the test bacteria. Spices used in Kachhila revealed that bacterial load decreased with time due to the antibacterial property of spices.
 Conclusion: This study concluded that the antibacterial effect of aqueous extract of Garlic extract was stronger in comparison, followed by Turmeric and Ginger against four test bacteria isolated from buff meat namely; E. coli, Salmonella spp., Pseudomonas spp., Staphylococcus aureus. Therefore this study revealed that spices used in Kachhila have an antibacterial property and enhance the shelf life of Kachhila.

In vitro anti-bacterial activity of aqueous extracts of the whole plant, flowers, roots, leaves and stem of grass Heteropogon contortus grown in Sri Lanka

In vitro antibacterial potential of aqueous extracts of Heteropogon contortus (whole plant, leaves, flowers, stem and roots) were examined against gram negative and positive pathogen; Escherichia coli (ATCC 25922) and Staphylococcus aureus (ATCC 25923) respectively. Concentrations tested were 100 and 200 mg/mL, using agar well diffusion bioassay technique. Gentamicin (1µg/mL) was used as the positive control and distilled water as the negative control. The results revealed that different parts of the plant exhibit different degrees of antibacterial activity. The ranking of the potency of antibacterial activity against Escherichia coli was whole plant > leaves > flowers > root > stem, while whole plant > flowers > roots > leaves > stem for Staphylococcus aureus. Phytochemical analysis revealed the presence of alkaloids, flavonoids, diterpenes and glycosides in certain parts of the plant while phenols, proteins and amino acids were found in all parts. The antibacterial activity is likely to be mediated by synergistic action via multiple mechanisms. A strong possibility exists to develop a safe and potent antibacterial agent from Heteropogon contortus.

Antibacterial Activity of Aqueous Extract of Momordica charantia and Terminalia catappa on Multidrug Resistant Invasive Escherichia coli isolated in Ready-to-Eat (RTE) Foods from Ekiti State


 Antibacterial activity of aqueous extract of Momordica charantia and Terminalia catappa was investigated against multidrug resistant invasive Escherichia coli isolated from ready-to-eat foods such as sausage rolls, meat pie, egg roll, doughnut and smoked fish. From the samples tested, smoked fish was found to have the highest microbial load of 1.05x106cfu/mL (55%) followed by meat pie 7.5x105cfu/mL (37%); Sausage roll 7.0x105cfu/mL (36%); and egg roll with 6.5x105cfu/mL (31%). Doughnut was found to have the lowest microbial load of 58x105cfu/mL (20%). The minimum inhibitory concentration (MIC) of the extract determined by agar dilution technique showed that M. charantia and T. catappa had an MIC of 0.5 g/mL and the degree of antibacterial potency of the extracts determined using broth dilution technique showed that at concentration of 0.5 mg/mL, M. charantia and T. catappa had diameter of zone of inhibition of 10.4mm and 11.2 mm, respectively. The observed antibacterial effect of the T. catappa was more pronounced. This investigation depicts positive results by the use of T. catappa extract in drug development for the treatment of infections caused by E. coli isolated from ready-to-eat foods.

Waste management of dark coniferous trees debarking for producing antibacterial preparations

The article presents the results of studying the antibacterial activity of fir tree and Siberian spruce bark water extracts. As test objects, pathogenic (3-4 hazard class) and saprotrophic bacteria were used. It has been shown that the studied aqueous extracts of dark-coniferous bark do not exhibit biocide activity against the conditionally pathogenic bacterium Escherichia coli. However, all the other studied bacteria are sensitive to the extracts analyzed both on day 3 and day 13. At the same time, the aqueous extract of the Siberian fir bark has a higher biocide activity against conditionally pathogenic and saprotrophic bacteria in comparison with the aqueous extract of the Siberian spruce bark. The antibacterial activity of aqueous extracts of the studied plants bark is determined by their chemical composition, primarily the presence of substances of a phenolic nature. It has been shown that the studied extracts mainly contain compounds of quercetin, dihydroquercetin and kaempferol.

English

Peganum harmala seed extract has been frequently reported to possess antibacterial potential through in vivo studies. P. harmala L. (Zygophyllaceae) is one of the most famous medicinal plants used in traditional medicine of Iraq. The harmaline, harmalol and harmine exerted many pharmacodynemic effects on the central nervous system: stimulation and depression depending on the dose. P. harmala indicates a great variety of pharmacological activities such as antimicrobial, antitumor, antinociceptive and monoamine oxidase (MNO) inhibitory activities. The most important components of P. harmala seeds are harmaline, vasicinone and deoxyrsinone. The antibacterial effect of P. harmala was studied. The antibacterial activity of aqueous extracts was determined by agar well diffusion method. It inhibited the growth of Escherichia coli and Staphylococcus aureus. All animals injected with 100 mg/kg b. w of aqueous extract of P. harmala show myorelaxation or incoordination; so the animals dropped down from the wire 3 consecutive times i n 60 s. Aqueous extract of P. harmala also induced muscle relaxation and prolonged the sleeping time induced by pentoparpitol. These data suggest that P. harmala extract could inhibit the growth of S. aureus and E. coli strain in vitro and this activity may contribute to its chemopreventive effect. Key words: Antibacterial, muscle relaxant, hypnotic, Peganum harmala.

Antibacterial Activity of Aqueous Extracts of Malus Domestica Against Some Bacterial Pathogens

The present study was designed to evaluate the antibacterial activity of aqueous extracts of Malus domestica (peel and pomace) against food-borne pathogens (Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Enterococcus feacalis). Extraction conditions (temperature and time) were optimized to obtain maximum yield by using response surface methodology. Antibacterial potentials of the extracts were examined through disc inhibition zone technique and the results were compared with commercial antibiotic. Results Indicated that maximum antibacterial activity was shown by peel extract against Staphylococcus aureus with average zone of inhibition 19.25±0.89 mm while pomace 12.75±0.71 mm. Maximum recovery for water soluble compounds from peel was obtained at 70ºC followed by 90ºC and 50ºC, which was 16.33, 14.67 and 12.67%, respectively. The extraction yield was also increased but after 30 minutes. The antibacterial activities of peel extract were comparable with commercial antibiotic (20.13±0.83 mm). Escherichia coli were appeared to be the most resistant with inhibition induced by the extracts of peel 15.00±1.07 mm and pomace11.50±0.53mm.