Antibacterial Activity Of Various Extracts Research Articles

Phytochemical analysis and evaluation of antibacterial activity of various extracts from leaves, stems and roots of Thalictrum foliolosum

Phytochemical analysis and evaluation of antibacterial activity of various extracts from leaves, stems and roots of Thalictrum foliolosum

DETERMINATION OF ANTIMICROBIAL ACTIVITY OF FRUITS OF CITRULLUS COLOCYNTHIS

Objective: The current study was designed to examine the antibacterial activity of various extracts of Citrullus colocynthis fruits against Helicobacter pylori, Salmonella enterica, Shigella flexneri, Campylobacter jejuni, Micoplasma pneumonia, and Shigella dysenteriae.Methodology: Antimicrobial activity was evaluated by agar disc diffusion method. The available genome of C. colocynthis was utilized to retrieve sequence of highly conserved genes matK, rpl20, rpl32, and rps7 and to identify their relevant genes in C. rehmii.Results and Conclusion: The maximum antimicrobial activity was shown by ethanol extract (S. f. 32mm, C. j. 27mm, H. p. 26mm, S. d. 22mm, M. p. 21mm, S. e. 19mm) while least activity was given by n-hexane extract (S. f. 13mm, C. j. 11mm, H. p. 18mm, S. d. 8mm, M. p. 10mm, S. e. 8mm) when compared with standard antibiotic levofloxacin (S. f. 30mm, C. j. 30mm, H. p. 30mm, S. d. 28mm, M. p. 25mm, S. e. 20mm). All extracts had given maximum response against H. pylori and S. flexneri and least response against M. pneumoniae and S. enterica. The in-silico genome-wide investigation studies showed that all four genes of C. rehmii were identified with high conservation based on motif distribution and phylogenetic relations.

Evaluation of Geum urbanum L. Extracts with Respect to Their Antimicrobial Potential

Preparations derived from roots and rhizomes of Geum urbanum L. are traditionally used for the treatment of ulcers and irritations of mucous membranes of the mouth, stomach, and intestinal tract. In complementary medicine, fermentation is one of the methods applied to recover plant extracts used for the production of such pharmaceutical preparations. The present study was performed to characterize the secondary metabolites and to evaluate the antimicrobial potential of different G. urbanum root and rhizome extracts. For this purpose, individual metabolites of fresh and fermented G. urbanum root and rhizome extracts were analyzed by HPLC-DAD-MSn and GC/MS. Among others, rare ellagitannin-sulfates could be characterized by LC/MSn . In addition, the antibacterial activity of various extracts of fresh and dried G. urbanum roots and rhizomes against Staphylococcus aureus (ATCC 6538) and Cutibacterium acnes (CP033842.1; FDAARGOS 503 chromosome) were assessed and compared to that of G. rivale. Furthermore, low- and high-molecular tannins were fractionated by column chromatography, demonstrating the latter to exhibit highest antibacterial activity.

An in vitro evaluation of antibacterial activity of various extracts of Achyranthes aspera and Cissus quadrangularis

The antibacterial activity of aqueous and methanol extracts of Achyranthes aspera and Cissus quadrangularis was evaluated. A. aspera and C. quadrangularis plants collected from its natural habitat in and around Tirunelveli, Tamil Nadu, India were shadow dried at room temperature and pulverized into coarse powder. Aqueous extracts were prepared by extracting with distilled water at 100°C for 4h and methanol extracts were prepared by maceration process using methanol for 72h. The aqueous extract yield was 12.1% and 23.5% for A. aspera and C. quadrangularis respectively. Whereas, methanol extract yield was 6% and 4% for A. aspera and C. quadrangularis, respectively. The antibacterial activity of plant extracts against Staphylococcus aureus (MTCC-96) and Escherichia coli (MTCC-443) was evaluated by Agar well diffusion method. The diameters of zone of inhibition ranged from 8mm to 17mm with highest inhibition zone observed against S. aureus by methanol extract of A. aspera (17mm) followed by aqueous extract of C. quadrangularis (13mm) and methanol extract of C. quadrangularis (9mm). Whereas, zone of inhibition (8mm) against Escherichia coli was observed only with methanol extract of C. quadrangularis. The results necessitate further study to isolate the active principles from the plant extracts to exploit the potential antibacterial activity and to find novel pharmacological uses of these plants beyond their racial use.

HPLC Quantification of Thymoquinone Extracted from Nigella sativa L. (Ranunculaceae) Seeds and Antibacterial Activity of Its Extracts against Bacillus Species.

The medicinal importance of Nigella sativa seeds for treating various ailments is portrayed by its traditional uses. Owing to its immense pharmacological importance, the thymoquinone phytoconstituent of N. sativa can prove beneficial for the South Asian countries including Pakistan, where this seed is commonly produced and healthcare facilities are limited. In this study, the antibacterial activity of various extracts of N. sativa seeds, extracted thymoquinone, and oil samples have been investigated against Bacillus subtilis and Bacillus licheniformis using well and disc diffusion assay. The inhibition zones ranged between 7 and 44 mm against both the bacterial strains by well diffusion assay, while disc diffusion assay provided inhibition zones in the range of 7–23 mm. Commercial and local Kalonji oil samples were included in the study. Oil samples dissolved in methanol showed increased inhibition of bacteria. However, the extracted thymoquinone showed highest antibacterial activity. Medicine formulated using thymoquinone will prove to be an herbal alternate against the resistant microbiota associated with bacterial infections. Antibacterial activity against some Bacillus species will help signify the effect on normal gut flora when oral therapy is followed. Trying different extraction protocols can help increase extraction efficiency. Study on extraction of thymoquinone in local produce of black seed can be fruitful for conducting the stability studies and can help to gain maximum benefits from the bioactives. The crude extracts from 10 g of these seeds were subjected to preliminary phytochemical investigation. Results showed that although methanol extract had the presence of maximum phytochemicals, hexane extract was the most potent in terms of antibacterial activity. Thymoquinone, a therapeutically important bioactive in N. sativa seed, was extracted employing both solvents. TLC assay and UV spectroscopy were used for its qualitative assessment, while HPLC-UV quantification showed that 250 mg/mL of methanol extract had 368.3 μg/mL thymoquinone, while its successive extraction yielded 32.94 μg/mL thymoquinone.

Antibacterial Activity of Various Extracts of Averrhoa bilimbi against Multidrug Resistant Bacteria

The multi-drug resistance (MDR) bacteria is a global health problem that causes high mortality every year. Therefore, novel antibacterial agents are needed from natural biological sources. This research aimed to investigate the antibacterial activities of various crude extracts of Averrhoa bilimbi against MDR bacteria. The antibacterial activity was calculated based on the use agar well diffusion assay and the minimum bactericidal concentration (MBC) using Mueller–Hinton broth in a microdilution method. Bacteria from wells were subcultured using inoculating loop onto a 5% sheep BAP. The best antibacterial activity, calculated as the most widely inhibitory zone and the smallest MBC values. The ethanolic extract showed antibacterial activity against the all MDR bacterial test in the agar well diffusion assay (10-14.5 mm inhibition diameter). The MBC of water extract against ESβL + CR Pseudomonas aeruginosa showed the best antibacterial activity (12.5 mg/mL). The fruit of bilimbi was shown to be potentially developed as antibacterial agents, especially for MDR strains. Further in vivo research and discovery of action mode are needed to shed light on their antibacterial effects. This study can provide new information about the benefits of bilimbi as a source of natural antibacterial againts MDR-bacteria

Antibacterial activity of different crude extracts of Suaeda maritima used traditionally for the treatment of hepatitis

Traditionally, plants and their products are used as a folk medicine for the treatment of curable and incurable diseases for a long time in many areas of the world. However, there is a lack of systematic study of the antibacterial activity of Suaeda maritima (S. maritima). The present study is to estimate the antibacterial activity of various extracts of newly discovered species S. maritima plant which is collected from Oman. The methanol extract was prepared by the Soxhlet method and it was fractionation by different solvents to give different crude extracts. The antibacterial activity was assessed by using the agar disc diffusion method in which the extracts at different concentrations were applied to the disc by putting them in sterile filter paper of about 6 mm. The agar discs were incubated for 24 h and measure the inhibition zone of antibacterial activity. The range of the inhibition zone was between 7 and 12 mm. Overall all concentrations of each extract of S. maritima showed inhibition activity against the applied bacterial strains. The results found that the hexane extract at all concentrations was possessed the highest activity against the used two Gram-positive and two Gram-negative bacteria strains. In conclusion, the highest antibacterial activity hexane extract from the S. maritima could be used for the treatment of infectious diseases. In addition, the observed antibacterial activity of the selected plant could be due to the presence of high contents various group bioactive compounds.

Antioxidant and antimicrobial activity of different plant parts of Anacardium occidentale L. and Mangifera indica L.: a comparative study

Anacardium occidentale L. and Mangifera indica L. has been used worldwide both for pharmaceutical, food and cosmetic industries due to the presence of biological activities of some of its metabolites. The present study comprises the correlation of antioxidant activity and antimicrobial activity in ethyl acetate extract of young leaves and bark of A. occidentale and M. indica. The activity of 1, 1-diphenyl-2-picrylhydrazyl (DPPH) on radical scavenging effect of the extracts was carried out by spectrophotometrically. All the plant extracts showed DPPH radical scavenging activity and among the extracts, A. occidentale young leaves indicated higher antioxidant potential in comparison with those of the other extracts. The antibacterial activity of various extracts was also screened against some human pathogens of clinical importance; Pseudomonas aeruginosa; Salmonella typhi; Bacillus subtilis; Escherichia coli and Staphylococcus aureus.

Antioxidant and antibacterial activities of various extracts of Inula cuspidata C.B. Clarke stem

The objective of the present study includes estimation of total phenolic and total flavonoid contents and evaluation of antioxidant and antibacterial activities of various extracts of Inula cuspidata stem. I. cuspidata belongs to family Compositae; it is an erect shrub, distributed in western Himalaya, usually found growing on steep rocky or precipitous ground.Total phenolic and flavonoid contents were estimated by Folin–Ciocalteu and aluminum chloride method. Antioxidant activity was performed by four methods: DPPH (1,1-diphenyl-2-picryl hydrazyl radical), ferrous chelating activity, reducing power and nitric oxide scavenging activity. These extracts were screened for antibacterial studies using macro-dilution method.Total phenolic and flavonoid contents were found to be highest in methanol extract (69.44 ± 1.12 mg GAE/g, 12.45 ± 0.67 mg QE/g) followed by chloroform (33.53 ± 0.88 mg GAE/g, 1.27 ± 0.51 mg QE/g) and n-hexane (12.25 ± 1.03 mg GAE/g, 0.08 ± 0.43 mg QE/g) extracts. Methanol extract of I. cuspidata exhibited potent antioxidant activity in all the antioxidant assays followed by chloroform and n-hexane extracts. IC50 values of methanol, chloroform and n-hexane extract were found to be 43.35 ± 0.58 µg/mL, 298.08 ± 0.62 µg/mL, 1989.24 ± 0.71 µg/mL for DPPH, 396.63 ± 0.73 µg/mL, 915.29 ± 0.81 µg/mL, 1180.56 ± 0.88 µg/mL for ferrous chelating and 594.68 ± 0.99 µg/mL, 930.55 ± 1.03 µg/mL, 1959.26 ± 1.25 µg/mL for nitric oxide scavenging assays. A strong correlation was found between total phenolic, flavonoid and 1/IC50 values obtained by different antioxidant assays. The correlation coefficient (R) value obtained was more than 0.9 which exhibits a strong correlation.All the extracts showed significant antibacterial activities against Gram positive bacterial strains with minimum inhibitory concentration (MIC) values ranging from 187.5 to 750 µg/mL and moderate to weak inhibition against Gram negative bacteria with MIC values ranging from 750 to 3000 µg/mL. The present study proves the in vitro anti-oxidant and antibacterial activities of different extracts of I. cuspidata stem.

Antimycobacterial and Antibacterial Activity of Allium sativum Bulbs.

Tuberculosis is one of the major public health problems faced globally. Resistance of Mycobacterium tuberculosis to antitubercular agents has called for an urgent need to investigate newer drugs to combat tuberculosis. Garlic (Allium sativum) is an edible plant which has generated a lot of curiosity throughout human history as a medicinal plant. Garlic contains sulfur compounds like allicin, ajoene, allylmethyltrisulfide, diallyltrisulfide, diallyldisulphide and others which exhibit various biological properties like antimicrobial, anticancer, antioxidant, immunomodulatory, antiinflammatory, hypoglycemic, and cardiovascular effects. According to various traditional systems of medicine, garlic is one of the established remedies for tuberculosis. The objective of the current study was to investigate in vitro antimycobacterial activity as well as anti-bacterial activity of various extracts rich in specific phytoconstituents from garlic. Preparation of garlic extracts was done based on the chemistry of the constituents and their stability. The estimation of in vitro antimycobacterial activity of different garlic extracts was done using Resazurin microtire plate assay technique whereas activity of garlic oil was evaluated by colony count method. The antibacterial activity of extracts and oil was estimated by zone of inhibition method. Extracts of garlic rich in allicin and ajoene showed appreciable antimycobacterial activity as compared to standard drugs. Garlic oil demonstrated significant antibacterial activity, particularly against methicillin-resistant Staphylococcus aureus.

Screening of Bactericidal Activity of Selected Plumbago Species Against Bacterial Pathogens

The present study was undertaken to determine the antibacterial potential of Plumbago species viz., Plumbago zeylanica Linn., Plumbago auriculata Lam. and Plumbago rosea Linn. collected from various localities of South India. For the bio-efficacy studies six different extracts of Plumbago species with various concentrations viz., 20, 40, 60, 80 and 100µg/ml against Gram positive and Gram negative bacterial pathogens viz., Staphylococcus aureus (MTCC 737), Streptococcus pyogenes (MTCC 1928), Bacillus subtilis (MTCC 441), Klebsiella pneumoniae (MTCC 109), Morganella morganii (MTCC 662) and Pseudomonas aeruginosa (MTCC 1688) using well diffusion method. Among the eighteen different extracts of three different Plumbago species, highest frequency of antibacterial activity (54%) was recorded in P. rosea. The antibacterial activity of various extracts in different concentration of the selected Plumbago species are as follows: P. rosea (54%) > P. zeylanica (49%) > P. auriculata (40%). The ethanolic extract of all the Plumbago species revealed superior bactericidal activity compared to other tested extracts. The ethanolic extracts of P. zeylanica, P. auriculata and P. rosea showed 91%, 50% and 99% of activity against Gram positive pathogens and 66%, 26% and 89% of activity against Gram negative pathogens. The bioactive compound plumbagin and extract of aerial parts of Plumbago species show a wide spectrum of antibacterial activity. The compound shows promise as a new drug for various bacterial infectious diseases. Hence, this study offers a base of using Plumbago species as herbal alternative for the synthesis of antimicrobial agents.

Antibacterial activities of bioactive compounds extracted from Marine algae Gracilaria salicornia against Aeromonas hydrophila

Herbal medicinal products have attracted significant research interest in recent years. Considering the efficiency of algae products in controlling pathogenic bacteria and also easy access to large resources of algae, this study was conducted to evaluate the effects of methanolic, chloroformic and aqueous extracts of Gracilaria salicornia against Aeromonas hydrophila , a heterotrophic, Gram-negative, rod-shaped bacterium found mainly in warm climate. Algae samples were collected from Qeshm Island coastlines and transferred to the laboratory. Standard methods were used to obtain the algae extract. Antibacterial activities of various extracts were tested against the bacterium using well diffusion assay method. Significant differences were observed in antibacterial activities of different extracts ( P <0.05). The diameter of zone of growth inhibition varied in correlation with concentration of the extracts (50, 100, 200 and 300 mg.ml -1 ). The best inhibition zone was observed at 100, 200 and 300 mg.ml -1 methanolic and 300 mg.ml -1 aqueous extracts.

Preliminary phytochemical screening and in vitro antibacterial activity of Anamirta cocculus (Linn.) seeds

The present work is aimed at primary screening of the phytochemical contents of seven solvents (petroleum ether, benzene, chloroform, acetone, methanol, ethanol and a mixture of methanol and ethyl acetate (1:3)) extracts of the seeds of Anamirta cocculus (Linn.) and to evaluate the antibacterial activity of these extracts against five species of pathogenic bacteria. The powdered seeds of A. cocculus were extracted with seven solvents (polar and non-polar) with Soxhlet apparatus and the extracts were subjected to preliminary phytochemical screening by standard biochemical tests. The antibacterial activity of various extracts was evaluated against five bacterial species (Staphylococcus aureus, Proteus vulgaris, Escherichia coli, Salmonella typhi and Klebsiella pneumoniae). The zone of inhibitions and minimum inhibitory concentration (MIC) of the various extracts were determined by running the experiments in triplicates. The extracts of the seeds of A. cocculus contained various pharmaceutically active substances viz., aldehydes, alkaloids, phenolic compounds, flavonoids, saponins, carbohydrates, proteins, lipids, glycosides, phytosterols, volatile oils, gums and mucilage and other minor phytochemicals. All the extracts showed significant levels of antibacterial activity. Methanol extract was the most active one with remarkable antibacterial activity on the various species tested. MICs of the extracts revealed methanol extract as the most potent one with the lowest inhibitory concentration of 3μg/mL on E. coli. The findings of the present study indicated that the seeds of A. cocculus possess various secondary metabolites having the potential for developing pharmaceutical drugs, especially antimicrobial ones.

Comparative Analysis of Antibacterial Properties and Chemical Composition of Glycyrrhiza glabra L. from Astrakhan Region (Russia) and Calabria Region (Italy)

We compared antibacterial activity of various extracts of two licorice subspecies against Staphylococcus aureus, Escherichia coli, and Bacillus subtilis. Diethyl carbonate extracts of Glycyrrhiza glabra root from Astrakhan region (Russia) exhibited maximum activity against the test microbial strains; activity of Astrakhan licorice was superior among 50% ethanol extracts from Astrakhan (Russia) and Calabria (Italy). Antibacterial activity is directly proportional to the content of glycyrrhizin and 18β-glycyrrhetinic acid in the extracts. According to preliminary data, the content of these chemical components in Glycyrrhiza glabra root from Astrakhan region is higher than in licorice growing in Italy, which is presumably related to climate and geographic characteristics of Astrakhan region.

English

The aim of this investigation was to evaluate the phytochemical, antibacterial and cytotoxic activities of ethanol extract and hexane, dichlorometane, ethyl acetate and hydroethanolic fractions from Aristolochia galeata&rsquo;s rhizomes. The minimum inhibitory concentration (MIC) and minimum lethal concentration (MLC) were evaluated by the broth microdilution assay to investigate the antibacterial activity of various extracts and fractions of A. galeata against Gram-positive and Gram-negative bacteria. The cytotoxicity of plant samples was evaluated in human cervix carcinoma cell line (HeLa) by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) colorimetric assay. The phytochemical study showed the presence of main secondary metabolites, steroids, flavonoids, coumarins and alkaloids. The ethanol extract and their fractions presented antimicrobial activity against Gram-positive bacteria, and Staphylococcus aureus was regarded the most sensitive strain with MIC of 250 &micro;g/ml for the ethanol extract. The dichlorometane fraction showed bactericidal activity with the value of 1250 &micro;g/ml and moderate cytotoxicity in front of the HeLa cell line tested (CC50 = 90 &micro;g/ml). The results showed that A. galeata had effective antibacterial activity against Gram-positive bacteria and compounds extracted from A. galeata Mart. ex Zucc could be used as possible antimicrobials. The good antimicrobial activity and the low cytotoxicity presented by the hexane fraction can be promised for the new molecules with antibiotic activity. Key words: Aristolochia galeata, antibacterial activity, minimal inhibitory concentration, cytotoxic activity, phytochemistry.

A pharmacognostical study of Vernonia cinerea Less (Asteraceae) and evaluation of anti-inflammatory and antibacterial activities of stem

Aim This study aimed to establish the pharmacognostical characteristics of leaf, stem and root of Vernonia cinerea, Asteraceae (ash-coloured fleabane), and to verify the anti-inflammatory and antibacterial activities of various extracts of the stem. Background V. cinerea (Asteraceae) is traditionally used to treat inflammation, diarrhoea, cough, smoking cessation, asthma, Parkinson's disease and leprosy. Materials and methods Leaf, stem and root and their powders were examined microscopically, and pharmacognostic standardization parameters were determined according to WHO guidelines. Extracts of different organs of the plant in petroleum ether, chloroform, ethanol, ethanol (50%) and water were prepared and examined by thin-layer chromatography. An antibacterial assay of the stem extracts for Staphylococcus aureus was performed. The anti-inflammatory activity of the same extracts was studied using a carrageenan-induced paw oedema model in Wistar rats. Results and conclusion Microscopic characterization of the different organs of the plant indicated the presence of trichomes, arrangement of vascular bundles (stem: radial, root: scattered), anomocytic and diacytic stomata, and wavy epidermal cells in stomata. The antibacterial assay indicated a zone of inhibition of 20 ± 0 and 19.33 ± 0.33 mm with alcoholic and chloroform extracts of V. cinerea leaf, respectively (extracts of stem showed a zone of inhibition of 21.00 ± 0.57 and 21.00 ± 0.57 mm, respectively). Diclofenac sodium and chloroform extract showed 11.11% inhibition of inflammation, whereas 16.66 and 13.33% inhibition were observed with alcoholic and hydroalcoholic extracts, respectively. Microscopic and pharmacognostic parameters aid in the identification and characterization of different organs of the plant. Traditional claims of antimicrobial and anti-inflammatory activities of the stem have been verified. Various extracts showed significant results for anti-inflammatory and antimicrobial action.

The Antibacterial and Phytochemical Aspects of Viola odorata Linn. Extracts Against Respiratory Tract Pathogens

Monitoring of susceptibility of herbal drugs for bacterial pathogens is important for appropriate choice of treatment. The present study was to evaluate the antibacterial activity of various extracts of Viola odorata against selected respiratory tract pathogens i.e. Haemophilus influenzae MTCC 3826, Pseudomonas aeruginosa MTCC 2474, Staphylococcus aureus MTCC 1144, Streptococcus pneumoniae MTCC 655 and Streptococcus pyogenes MTCC 442. Plants were collected from Herbal Nursery, Prem Nagar Ashram, Haridwar, Uttarakhand and authenticated at Botanical Survey of India, Northern Regional Center, Dehradun. Properly washed and shade dried aerial parts of the plant material were crushed and extracted in petroleum ether, acetone, methanol and water by using Soxhlet apparatus. The antibacterial activity was examined by agar well diffusion method and the minimum inhibitory concentration (MIC) by twofold serial dilution method. Erythromycin was used as positive control to determine the sensitivity of the strains. The results showed that methanol extract was more active than other extracts in its antibacterial activity. The zone of inhibition exhibited by methanol extract against tested microorganisms ranged between 16 mm to 24 mm respectively. MIC values were recorded between 3.12 mg/ml to 12.5 mg/ml for all the organisms. Phytochemical analysis of methanolic extract revealed the presence of flavonoids, glycosides, alkaloids, steroids, saponins and tannins. The investigation supports a good response to the use of V. odorata in herbal medicine and as a base for the development of new drugs and phytomedicine in rationale for its use in treatment of respiratory infectious diseases.

Antioxidant, Antimicrobial, and Free Radical Scavenging Potential of Aerial Parts ofPeriploca aphyllaandRicinus communis

Context. Many diseases are associated with oxidative stress caused by free radicals. Objective. The present study evaluated the in vitro antioxidant and antibacterial activities of various extracts of aerial parts of Periploca aphylla and Ricinus communis. Materials and Methods. In vitro antioxidant activities of the plant extract were determined by DPPH and NO scavenging method. Superoxide anion radical activity was measured by the reduction of nitro blue tetrazolium as compared with standard antioxidants. Total phenolic contents and antibacterial activities of these plants were determined by gallic acid equivalent (GAE) and serial tube dilution method, respectively. Results. Plants showed significant radical scavenging activity. The results were expressed as IC50. n-Propyl gallate and 3-t-butyl-4-hydroxyanisole were used as standards for antioxidant assay. All the extracts of both plants showed comparable IC50 to those of standards. Plants extract exhibited high phenolic contents and antibacterial activities were comparable with standard drug, Ciprofloxacin. Discussion and Conclusion. The present study provides evidence that Periploca aphylla and Ricinus communis prove to be potent natural antioxidants and could replace synthetic antioxidants. Plants can also be used against pathogenic bacterial strains.

Antibacterial activities of extracts of leaf, fruit, seed and bark of Phoenix dactylifera

The antibacterial activities of different parts of local Phoenix dactylifera were investigated in vitro. Dried leaf, fruit, seed and tree bark were extracted with water, methanol and acetone. Antibacterial property of the extracts was evaluated against Staphylococcus aureus , Streptococcus pyogenes, Escherichia coli and Pseudomonas aeruginosa using the disc diffusion method. Overall analysis of the antibacterial activity of various extracts revealed that the highest inhibitory activity was produced by the fruit extract (18.2 ± 0.55 mm) as compared to the leaf, bark and seed extracts. All the extracts from the different parts of the plant showed antibacterial activity against most tested microorganisms. On the whole, aqueous extracts have the least antibacterial activity as compared to methanol and acetone extracts. The antibacterial activity against the Gram-positive strains was the highest in the acetone fruit extract against S. aureus (18.2 ± 0.55 mm). The most active extract against Gram-negative bacteria was methanol extract from the leaves with a 13.5 ± 0.33 mm inhibition zone for E. coli followed by 12.5 ± 0.88 mm for P. aeruginosa. Phytochemical analysis revealed the presence of carbohydrates and alkaloids in all parts, and flavonoids, steroids, saponins and tannins were present in some parts. Key words : Antibacterial activity, Phoenix dactylifera, disc diffusion assay, extracts, inhibition zone.

Therapeutical Effect of Extracts of Terminalia chebula In Inhibiting Human Pathogens and Free Radicals

In recent years, multiple drug resistance has been developed due to indiscriminate use of existing antimicrobial drugs in the treatment of infectious diseases. Conventional antibiotics are strong medicines, which if not used in precise way may cause harmful effects. The major thrust is to establish alternative antimicrobial agent in order to treat microbial infections with less or no toxic effect to body and less negligible side effects. The herbal medicines have shown potential to overcome the limitation associated with conventional drugs. However, the appropriate choice of source for herbal medicine is also very important. Terminalia chebula possesses potential pharmaceutical activities and used in several Ayurvedic formulations. The study of solvent-free organic (ethylacetate, acetone, methanol of increasing polarity) and aqueous extracts of the fruits of T. chebula, showed the potential to reduce growth of microorganisms, minimizing the risk of infection, while optimizing the conditions to encourage healing. In our study we found, methanol extract as a potential bactericidal and potent antioxidant while aqueous extract showed the least potential as an antimicrobial agent, though a moderate antioxidant. The finding may provide scientific rationale for the use of crude extract of the plant as a new drug compound as potential antioxidant and antimicrobial agent. Terminalia chebula is used as a mild laxative and as an astringent against wounds and abscesses. Practictioners of folk medicine in India and Southeast Asia use the fruit for homeostatic, laxative and as cardiotonic. It is used as a remedy against a sore throat and cough, against diarrhoea connected with a prolapsed rectum in China and against ulcers and dysentery in Tibet. The antibacterial activity of various extracts of Chebula myrobalan powder was tested against Streptococcus species, Staphylococcus aureus and Pseudomonas aeruginosa. II. MATERIALS T. chebula powder was purchased from local market of Mumbai, India. Pathogens of MTCC grade were obtained from IMTECH (Chandigarh, India). Gallic acid and Glutaraldehyde was purchased from s.d. fine-chemicals limited (Mumbai, India). Gentamicin and 2,4,6-tripyidyl-s-triazine (TPTZ) were procured from Hi-Media(Mumbai,India), 3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyl tetrazolium bromide (MTT, 98%) reagent, 4'-6-diamidino-2-phenylindole (DAPI), propidium iodide (PI) and nystatin was purchased from Sigma (St. Louis, USA). Fetal bovine serum (FBS) and streptomycin-penicillin antibiotic solutions were bought from HyClone (Utah, USA). All other chemicals used were of analytical grade. SIRC (rabbit corneal epithelial cells) cell line was obtained from NCL, Pune, India