Antagonistic activity of marine bacterial isolates on common human pathogenic bacteria

2017 ◽  
Vol 1 (2) ◽  
Author(s):  
Mukesh Pimpliskar ◽  
Priyanka Pagare ◽  
Rahul Jadhav

Antagonistic activity of marine bacteria against common human pathogens was studied in this project. Marine animal surface bacterial flora was isolated from selected animal collected from local fishermen. The sample bacteria were isolated by serial dilution followed by spread plate method using marine agar (ZMA). About 11 bacterial isolates were selected and screened for antimicrobial activity through agar well diffusion assay. Among 11 isolates, 7 isolates exerted an inhibitory effect against human pathogenic organisms (E.coli, S.aureus, Klebsiella and Candida sp.). The isolates were then investigated for antibiotic production by cross species signal transfer mediated induction, 2 isolates (Sh-2 and PJR-3) exhibited enhanced activity against human pathogenic organisms (E.coli, S.aureus and Candida sp.). These 2 isolates were characterized phenotypically by morphological techniques (which revealed the strains as gram-positive and gram negative respectively) and physiologically by conventional tests. 

2020 ◽  
Vol 49 (4) ◽  
pp. 415-423
Author(s):  
B. Baráti-Deák ◽  
Cs. Mohácsi-Farkas ◽  
Á. Belák

Bacterial strains with inhibitory effect on Salmonella Hartford, Listeria monocytogenes, Yersinia enterocolitica, and Escherichia coli, respectively, were isolated. Out of the 64 bacteria originated from food processing environments, 20 could inhibit at least one of the tested pathogens, and it was proved that growth decline of the pathogenic bacteria was more remarkable by co-culturing than by using cell-free supernatants of the isolates. Seven different genera (Pseudomonas, Bacillus, Paenibacillus, Macrococcus, Staphylococcus, Serratia, and Rothia) reduced the pathogens’ growth during the time period of analysis, and the strongest inhibitory effect was observed after 24 h between 15 and 30 °C. Sensitivity of the tested human pathogenic bacteria against the inhibitory strains was distinct, as Y. enterocolitica could be inhibited by numerous isolates, while S. Hartford proved to be the most resistant. Our results reveal that the isolated bacteria or their excreted metabolites could hinder pathogen growth when used in sufficient quantities.


2009 ◽  
Vol 6 (4) ◽  
pp. 627-632
Author(s):  
Baghdad Science Journal

In this part of programme , different bacterial isolates mainly Salmonella spp, Shigella spp and Escherichia coli were used for antagonism with Saccharomyces boulardii under different conditions . S.boulardii was grown under aerobic conditions and antagonized with young overnight nutrient broth cultures of test bacterial isolates and other kept in refrigerator for a week after full growth . Young cultures were more susceptible to antagonistic effect of yeast compared to old cultures and on isolates grown on solid medium for 24 hr. S.boulardii grown under aerobic and microaerobic conditions and antagonized with overnight broth cultures of test bacterial isolates , The results revealed that aerobic cultures of yeast had more inhibitory effect on test isolates .Concentration of yeast cells from liquid media GS( prepared from soluble fraction of gluten and mixed with equal volume of corn steep water and GS2%) was found not to be exceeded 109 yeast cell/ ml of suspension due to the large size of yeast cells .Effect of freezing on viability of yeast cells grown in GS and GS2% was negligible and there was no significant differences since the difference was less then half log cycle


Biologia ◽  
2007 ◽  
Vol 62 (1) ◽  
Author(s):  
Ali Bahar ◽  
Zihni Demirbağ

AbstractThe bacterial flora of the Oberea linearis (Coleoptera: Cerambycidae) was investigated and 13 different bacteria were isolated from O. linearis larvae. Seven of these bacteria were performed and characterized at species level and the rest of them were characterized at genus level. In this study, we determined morphological and physiological characteristics of the bacterial isolates by conventional and routine techniques, biochemical properties and metabolic enzyme profiles by API20E and Phoenix 1000A panel test systems. Additionally, 16S rRNA gene sequence analysis was also performed to identify the isolates at the molecular level. The isolates were identified as Acinetobacter calcoaceticus (Ol1), Enterobacter aerogenes (Ol2), Pseudomonas sp. (Ol3), Flavobacterium sp. (Ol4), Microbacterium sp. (Ol5), Enterobacter agglomerans (Ol6), Xanthomonas sp. (Ol7), Pseudomonas syringae (Ol8), Pseudomonas sp. (Ol9), Xanthomonas sp. (Ol10), Enterobacter cancerogenus (Ol11), Xanthomonas maltophilia (Ol12), and Serratia marcescens (Ol13). This is the first record of bacterial isolates (Ol5, Ol8, Ol11, Ol12) from any insect. All these bacteria were tested against O. linearis larvae, and Serratia marcescens was found to cause the highest mortality (65%). On the other hand, we determined 90% mortality against this pest within four days by utilizing spore and crystal mixture of Bacillus thuringiensis isolated from Melolontha melolontha.


2017 ◽  
Vol 2017 ◽  
pp. 1-6 ◽  
Author(s):  
J. M. Mutua ◽  
C. G. Gitao ◽  
L. C. Bebora ◽  
F. K. Mutua

This study was designed to determine antimicrobial resistance profiles of bacteria isolated from the nasal cavity of healthy camels. A total of 255 nasal samples (swabs) were collected in Isiolo, Samburu, and Nakuru counties, Kenya, from which 404 bacterial isolates belonging to various genera and species were recovered. The bacterial isolates included Bacillus (39.60%), coagulase-negative Staphylococcus (29.95%), Streptococcus species other than Streptococcus agalactiae (25.74%), coagulase-positive Staphylococcus (3.96%), and Streptococcus agalactiae (0.74%). Isolates were most susceptible to Gentamicin (95.8%), followed by Tetracycline (90.5%), Kanamycin and Chloramphenicol (each at 85.3%), Sulphamethoxazole (84.2%), Co-trimoxazole (82.1%), Ampicillin (78.9%), and finally Streptomycin (76.8%). This translated to low resistance levels. Multidrug resistance was also reported in 30.5% of the isolates tested. Even though the antibiotic resistance demonstrated in this study is low, the observation is significant, since the few resistant normal flora could be harboring resistance genes which can be transferred to pathogenic bacteria within the animal, to other animals’ bacteria and, most seriously, to human pathogens.


2017 ◽  
Vol 14 (4) ◽  
pp. 727-734 ◽  
Author(s):  
Baghdad Science Journal

Most approaches to combat antibiotic resistant bacteria concentrate on discovering new antibiotics or modifying existing ones. However, one of the most promising alternatives is the use of bacteriophages. This study was focused on the isolation of bacteriophages that are specific to some of commonly human pathogens namely E. coli, Streptococcus pyogenes, Staphylococcus aureus, Proteus mirabilis, Pseudomonas aeruginosa, Salmonella spp. and Klebsiella pneumoniae. These bacteriophages were isolated from sewages that were collected from four different locations in Kirkuk City. Apart from S. pyogenes, bacteriophages specific to all tested bacteria were successfully isolated and tested for their effectiveness by spot test. The most effective bacteriophages that were isolated from sewages and sewage water of Al-Jumhori Hospital compared to other sites. It is concluded that the sewage water of hospitals represents a perfect environment for these bacteriophages.


2017 ◽  
Vol 2017 ◽  
pp. 1-13 ◽  
Author(s):  
Donyez Frikha Dammak ◽  
Ziad Zarai ◽  
Soumaya Najah ◽  
Rayed Abdennabi ◽  
Lassaad Belbahri ◽  
...  

This study has focused on the isolation of twenty-three halophilic actinomycetes from two ponds of different salinity and the evaluation of their ability to exert an antimicrobial activity against both their competitors and several other pathogens. From the 23 isolates, 18 strains showed antagonistic activity, while 19 showed activities against one or more of the seven pathogen strains tested. Six strains exhibited consistent antibacterial activity against Gram-negative and Gram-positive pathogens characterized at the physiological and molecular levels. These strains shared only 94-95% 16S rRNA sequence identity with the closely related species of the Thermoactinomycetaceae family. Among them, the potent strain SMBg3 was further characterized and assigned to a new genus in the family for which the name Paludifilum halophilum (DSM 102817T) is proposed. Sequential extraction of the antimicrobial compounds with ethyl acetate revealed that the crude extract from SMBg3 strain had inhibitory effect on the growth of the plant pathogen Agrobacterium tumefaciens and the human pathogens Staphylococcus aureus, Salmonella enterica, Escherichia coli, and Pseudomonas aeruginosa. Based on the HRESI-MS spectral data, the cyclic lipopeptide Gramicidin S and four cyclic dipeptides (CDPs) named cyclo(L-4-OH-Pro-L-Leu), cyclo(L-Tyr-L-Pro), cyclo(L-Phe-L-Pro), and cyclo(L-Leu-L-Pro) were detected in the fermentation broth of Paludifilum halophilum. To our knowledge, this is the first report on the isolation of these compounds from members of the Thermoactinomycetaceae family.


Bionatura ◽  
2021 ◽  
Vol 6 (4) ◽  
pp. 2270-2273
Author(s):  
Lina Qays Yaseen ◽  
Sura Hameed Nayyef ◽  
Nadia Ibraheem Salih

In most underdeveloped nations, traditional medicine, including herbal treatment, is still widely used. Due to the growth of antibiotic resistance, this study aims to use pepper as an anti-bacterial as alternative to antibiotics. Pepper is one of the most important plants used as a medicine for a long time in various countries and civilizations. This study aims to use pepper as an anti-bacterial in alternative to antibiotics. The current study included the inhibitory efficacy of aqueous and alcoholic red pepper extract on seven bacterial isolates: -Staphylococcus aureus, Streptococcus spp, Escherichia coli, Klebseilla spp, Salmonella spp, Pseudomonas aeruginosa, Proteus spp. These isolates were isolated from different pathologies and regions, and they were diagnosed according to the site of infection. Several antibiotics were also used as a standard control sample for germs. This study shows that the highest inhibitory Effect against E. coli bacterium, as the average inhibition diameter was about 16.5 mm, and it is an excellent inhibitory when compared to the antagonist's gentamicin and nitrofurantoin as it showed good inhibitory efficacy against the bacteria such as S. aureus P. aeruginosa, and Salmonella spp. While the effect on Klebsiella was equal, on the other hand, the aqueous extract did not show any efficacy against Proteus spp, as was shown in the results. The results also showed that Staph. Aureus bacteria were the most affected by the alcohol extract of the red pepper as it showed a high inhibition zone compared with the control sample tetracycline and nitrofurantoin. The plant's aqueous and alcoholic red pepper extracts were effective against the tested bacterial isolates. The plant's aqueous and alcoholic red pepper extract has good inhibitory efficacy against the studied bacterial isolates.


Author(s):  
K. F. Williams ◽  
O. K. Agwa ◽  
G. O. Abu ◽  
O. Akaranta

Sophorolipid have been identified to possess varying antagonism relationship to a number microbiota, although having been identified as being ecologically friendly. The biosafety of biologically synthesized materials has been identified as a major challenge to commercialization and scale-up. Sophorolipid was produced by Candida haemulonis and Saccharomyces cerevisiae in Palm oil mill effluent impacted soil in Emohua, Rivers State. Submerged fermentation was employed in the production of the sophorolipid while the Well-in-agar approach was employed in the antimicrobial susceptibility was conducted using 20%, 40%, 60%, 80% and 100% on both beneficial and pathogenic bacteria and fungi namely Staphylococcus sp, Nitrobacter sp, Klebsiella sp, Bacillus sp while the fungal flora were Aspergillus sp, Penicillium sp, Rhizopus sp, Candida sp, Mucor sp and Saccharomyces sp. Acute toxicity was conducted using Nitrobacter sp, Nitrosomonas sp and Thiobacillus sp. Probit based determination of acute toxicity after a 48hr and 96hr exposure to the test organisms. Antagonistic nature of the sophorolipids showed there was little or no antagonistic activity on the bacterial isolates than the fungal isolates. The sophorolipid formulation synthesized from both isolates were observed to have a zone of inhibition between 10 mm to 24 mm for Nitrosomonas sp. while to Aspergillus sp it had a range between 4.0 mm to 13.0 mm. Acute toxicity of sophorolipid produced by Candida haemulonis against Nitrosomonas sp 0.054 mg/L while to Thiobacillus sp it had an acute toxicity index of 0.107 mg/L.  This study identified that the sophorolipid produced by the yeast isolate had the potential of being employed in a number of sectors. This study has pioneered the untapped benefits in the POME-induced flora and how they can be veritable tools in the biotechnology industry.


2020 ◽  
Vol 11 ◽  
pp. 37-43
Author(s):  
Prof. Teodora P. Popova ◽  
Toshka Petrova ◽  
Ignat Ignatov ◽  
Stoil Karadzhov

The antimicrobial action of the dietary supplement Oxidal® was tested using the classic Bauer and Kirby agar-gel diffusion method. Clinical and reference strains of Staphylococcus aureus and Escherichia coli were used in the studies. The tested dietary supplement showed a well-pronounced inhibitory effect against the microbial strains commensurable with that of the broad-spectrum chemotherapeutic agent Enrofloxacin and showed even higher activity than the broad spectrum antibiotic Thiamphenicol. The proven inhibitory effect of the tested dietary supplement against the examined pathogenic bacteria is in accordance with the established clinical effectiveness standards for antimicrobial agents.


Author(s):  
ANNAMALAI MADURAM ◽  
RAJU KAMARAJ

Objectives: The objectives of the study were to study the antibacterial activity for the various extracts of Clausena dentata against human pathogens. Clausena (Rutaceae) is a genus of about 23 species of unarmed trees and shrubs. The stem bark of C. dentata is used in veterinary medicine for the treatment of wounds and sprains. Even though C. dentata has a lot of potential medical uses, the study of microbiological properties is very scarce. Methods: The plant C. dentata was collected from Kadagaman, near Tiruvannamalai, Tamil Nadu, India, and authenticated by Centre for Advanced Study in Botany, University of Madras, Chennai. The dry powder of stem bark was extracted with hexane, chloroform, and methanol. The extracts were subjected to qualitative phytochemical screening and antibacterial activity against human pathogenic bacteria such as Escherichia coli, Salmonella Typhi, Klebsiella pneumonia, Vibrio cholerae, and Staphylococcus aureus and compared with ciprofloxacin. Results: Qualitative chemical tests revealed the presence of various phytochemicals such as alkaloids, glycosides, carbohydrate, proteins and amino acids, phytosterols, and volatile oil. The antibacterial activity result reveals that all the extracts were are more active against V. cholerae. The activity against Pseudomonas aeruginosa was mild. Conclusion: The activity against V. cholerae was comparable with that of 5 μg/mL ciprofloxacin at the concentration of C. dentata 40 μg/mL. The orders of antibacterial activity against human pathogenic bacteria are hexane, methanol, and chloroform extract of C. dentata.


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