scholarly journals Screening of active antimicrobial and biological enzymes of microbial isolated from soil in Thailand

Author(s):  
Pannapa Powthong ◽  
Apichai Sripean ◽  
Pattra Suntornthiticharoen

Objective: The objectives of this study were to isolate microorganisms and screen for potential antimicrobial activities from the soil. Methods: In this study, a total of 425 isolates were isolated from 100 soil samples. The preliminary screening for antimicrobial activities of these isolates was performed by modified cross-streak, agar diffusion, and modified icrodilution technique against 16 pathogenic bacteria and fungi.Results: In the anti-microbial activity, there were three isolates, namely, 277, 303, and 307 exhibited inhibitory activity against methicillin-resistantStaphylococcus aureus and Salmonella typhimurium respectively. This study also examined the various enzymes producing from soil microorganisms including chitinase, chitosanase, amylase, cellulose, caseinase, gelatinase, esterase, and lipase production of different selective media for 24 and 48hrs using the direct spot method. The results revealed that 28 isolates could produce various enzymes with strong activity. Most of them produced gelatinase (5.65%) and caseinase (5.18%). There were four isolates that produce broad-spectrum enzyme. In addition, the investigation of selectedmicroorganism identification showed that they can be divided into three groups: Burkholderia spp., Pseudomonas spp., and Rhodococcus spp.Conclusion: This study demonstrated that the microorganisms from soil are capable of producing potential, antibacterial, and bioactive enzymes.Keywords: Antimicrobial activity, Extracellular enzyme, Soil microbial, Drug-resistant bacteria.

Author(s):  
Pannapa Powthong ◽  
Pattra Suntornthiticharoen

Objective: Our study was to isolate Bacillus spp. from soil all around 6 geographic parts of Thailand and screen for potential antimicrobial.Methods: A total of 43 isolates which isolated from 100 samples of soil were investigated. Preliminary screening was based on antimicrobial activity against 16 strains of pathogenic bacteria and fungi, including 10 strains of Methicillin-resistant Staphylococcus aureus (MRSA), and 1 strain of Methicillin-sensitivity Staphylococcus aureus (MSSA), Extended spectrum beta lactamases (ESBL) Escherichia coli, Samonella Typhymurium, Klebsiella pneumoniae, Candida albicans, Cryptococcus neoformans respectively by cross streak, agar diffusion and modified microdilution technique. Moreover, the selected Bacillus spp. were then screened for bioactive enzyme, including chitinese, chitosanese, amylase, cellulose, caseinase, gelatinase, esterase and lipase production of different selective media for 24 and 48 h by direct spot agar.Results: There are 2 isolates, namely 23 and 49 showed particularly strong activity inhibitions against MRSA and pathogenic C. albicans. The diameter of hydrolysis zone results from screened for bioactive enzyme revealed that there were 36 isolate showed particularly strong activities with a broad spectrum enzyme. The isolate which produced the widest diameter hydrolysis zone in gelatin, cellulose and starch are 294, 303, and 290 respectively.Conclusion: Our result indicated Bacillus spp. from soil in Thailand showed potent antibacterial activity and bioactive compounds production.


Antibiotics ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 712
Author(s):  
Ali Salama ◽  
Ammar Almaaytah ◽  
Rula M. Darwish

(1) Background: Antimicrobial resistance represents an urgent health dilemma facing the global human population. The development of novel antimicrobial agents is needed to face the rising number of resistant bacteria. Ultrashort antimicrobial peptides (USAMPs) are considered promising antimicrobial agents that meet the required criteria of novel antimicrobial drug development. (2) Methods: Alapropoginine was rationally designed by incorporating arginine (R), biphenylalanine (B), and naproxen to create an ultrashort hexapeptide. The antimicrobial activity of alapropoginine was evaluated against different strains of bacteria. The hemolytic activity of alapropoginine was also investigated against human erythrocytes. Finally, synergistic studies with antibiotics were performed using the checkerboard technique and the determination of the fractional inhibitory index. (3) Results: Alapropoginine displayed potent antimicrobial activities against reference and multi-drug-resistant bacteria with MIC values of as low as 28.6 µg/mL against methicillin-resistant S. aureus. Alapropoginine caused negligible toxicity toward human red blood cells. Moreover, the synergistic studies showed improved activities for the combined conventional antibiotics with a huge reduction in their antimicrobial concentrations. (4) Conclusions: The present study indicates that alapropoginine exhibits promising antimicrobial activity against reference and resistant strains of bacteria with negligible hemolytic activity. Additionally, the peptide displays synergistic or additive effects when combined with several antibiotics.


Author(s):  
Prabhurajeshwar C. ◽  
Kelmani Chandrakanth R.

<p><strong>Objective: </strong>Probiotic products consist of specific strains of live bacteria that have potentially favorable health effects. A number of studies provide evidence that milk products with probiotics may be beneficial for digestive health and may improve various digestive problems. The purpose of the present study was to investigate <em>Lactobacillus</em> species with potential activities isolated from different cheese samples of local market.</p><p><strong>Methods: </strong>A total 42 lactic acid bacteria strains were isolated, fourteen (14/42) best <em>Lactobacillus</em> isolates were selected by preliminary screening as potential probiotics with antimicrobial activity against pathogenic bacteria. All the fourteen <em>Lactobacillus</em> isolates were then characterized <em>in vitro</em> for their probiotic features and antimicrobial activities against pathogens.</p><p><strong>Results: </strong>The results noticed that all selected <em>Lactobacillus</em> isolates (CH3, CH4 and CH6) were screened and confirmed as <em>Lactobacillus. </em>The isolates were able to grow at different pH, NaCl and bile salts, also exhibited the best antimicrobial activities against pathogens. All the isolates were susceptible to antibiotics used and isolates were also revealed the noticeable aggregation and hydrophobicity studies.<strong></strong></p><p><strong>Conclusion: </strong>Selected <em>Lactobacillus </em>isolates were considered as ideal, effective probiotic bacteria. Thus, they could be examined further and contribute to preventing and controlling several infections associated with intestine and for human health benefits.</p>


2020 ◽  
Author(s):  
Audrey Reuter ◽  
Cécile Hilpert ◽  
Annick Dedieu-Berne ◽  
Sophie Lematre ◽  
Erwan Gueguen ◽  
...  

AbstractThe global emergence of drug-resistant bacteria leads to the loss of efficacy of our antibiotics arsenal and severely limits the success of currently available treatments. Here, we developed an innovative strategy based on Targeted-Antibacterial-Plasmids (TAPs) that use bacterial conjugation to deliver CRISPR/Cas systems exerting a strain-specific antibacterial activity. TAPs are highly versatile as they can be directed against any specific genomic or plasmid DNA using the custom algorithm (CSTB) that identifies appropriate targeting spacer sequences. We demonstrate the ability of TAPs to induce strain-selective killing by introducing lethal double strand breaks (DSBs) into the targeted genomes. TAPs directed against a plasmid-born carbapenem resistance gene efficiently resensitise the strain to the drug. This work represents an essential step towards the development of an alternative to antibiotic treatments, which could be used for in situ microbiota modification to eradicate targeted resistant and/or pathogenic bacteria without affecting other non-targeted bacterial species.


Molecules ◽  
2020 ◽  
Vol 25 (22) ◽  
pp. 5256
Author(s):  
Andrea Locke ◽  
Sean Fitzgerald ◽  
Anita Mahadevan-Jansen

Bacterial infection is a global burden that results in numerous hospital visits and deaths annually. The rise of multi-drug resistant bacteria has dramatically increased this burden. Therefore, there is a clinical need to detect and identify bacteria rapidly and accurately in their native state or a culture-free environment. Current diagnostic techniques lack speed and effectiveness in detecting bacteria that are culture-negative, as well as options for in vivo detection. The optical detection of bacteria offers the potential to overcome these obstacles by providing various platforms that can detect bacteria rapidly, with minimum sample preparation, and, in some cases, culture-free directly from patient fluids or even in vivo. These modalities include infrared, Raman, and fluorescence spectroscopy, along with optical coherence tomography, interference, polarization, and laser speckle. However, these techniques are not without their own set of limitations. This review summarizes the strengths and weaknesses of utilizing each of these optical tools for rapid bacteria detection and identification.


2014 ◽  
Vol 70 (a1) ◽  
pp. C714-C714
Author(s):  
Calvin Steussy ◽  
Cynthia Stauffacher ◽  
Mark Lipton ◽  
Mohamed Seleem

The emergence of multi-drug resistant pathogenic bacteria is one of the great challenges to modern medicine. The gram positive cocci Methicillin Resistant Staphylococcus aureus (MRSA) and Vancomycin Resistant Enterococcus faecalis (VRE) are two particularly virulent examples. In vivo studies have shown that the eukaryotic like 'mevalonate' isoprenoid pathway used by these pathogenic cocci is essential to their growth and virulence [1]. Our structures of HMG-CoA reductase (HMGR) from P. mevalonii demonstrated that the bacterial enzymes are structurally distinct from the human enzymes allowing for specific antibacterial activity [2]. High throughput in vitro screening against bacterial HMGR at the Southern Research Center, Birmingham, AL uncovered a lead compound with an IC50 of 80 µM with a competitive mode of action. Our x-ray crystal structures of HMGR from E. faecalis complexed with the lead compound and its variations have informed the synthesis of new inhibitors that have improved the IC50 to 5 µM [3]. Studies of this compound show it to be active against both MRSA and VRE in culture, effective against these bacteria in biofilms, and efficacious in a model system of eukaryotic infection. Structures and kinetics of these compounds will be presented and future directions discussed.


PLoS ONE ◽  
2021 ◽  
Vol 16 (12) ◽  
pp. e0256936
Author(s):  
Ewa Stańczyk-Mazanek ◽  
Longina Stępniak

The paper discusses the analysis of the effect of using sewage sludge for fertilization on the level of soil and groundwater contamination with drug-resistant bacteria. Other sanitary contaminants in these environments were also analysed. Composted sewage sludge was introduced into the sandy soil over a period of 6 months. The examinations were conducted under conditions of a lysimetric experiment with the possibility of collecting soil leachates (in natural conditions). The following doses of sewage sludge were used: 0, 10, 20, 30 and 40 t/ha calculated per experimental object containing 10 kg of sandy soil. The research were carried out within the time frame of one year. Dactylis glomerata grass was grown on the fertilized soils. In soils and leachates from soils (which may have polluted groundwater) collected from fertilized experimental objects, the sanitary condition and quantity of drug-resistant bacteria (mainly from the families Enterobacteriaceae and Enterococcus) were analysed one year after fertilization. Their drug resistance to selected antibiotics was also analysed based on current recommendations. The study showed that fertilization with sewage sludge (even after stabilization and hygienization) results in contamination of soil and infiltrating waters with many species of drug-resistant pathogenic bacteria. The lowest level of contamination of soil and water environment was found after the application of sewage sludge at a dose of 10 t/ha. The isolated drug-resistant strains of intestinal bacteria were less sensitive to older generations of antibiotics including cefazolin, ampicillin, and co-amoxiclav.


2015 ◽  
Vol 60 (3) ◽  
pp. 1194-1201 ◽  
Author(s):  
G. L. Drusano ◽  
William Hope ◽  
Alasdair MacGowan ◽  
Arnold Louie

We are in a crisis of bacterial resistance. For economic reasons, most pharmaceutical companies are abandoning antimicrobial discovery efforts, while, in health care itself, infection control and antibiotic stewardship programs have generally failed to prevent the spread of drug-resistant bacteria. At this point, what can be done? The first step has been taken. Governments and international bodies have declared there is a worldwide crisis in antibiotic drug resistance. As discovery efforts begin anew, what more can be done to protect newly developing agents and improve the use of new drugs to suppress resistance emergence? A neglected path has been the use of recent knowledge regarding antibiotic dosing as single agents and in combination to minimize resistance emergence, while also providing sufficient early bacterial kill. In this review, we look at the data for resistance suppression. Approaches include increasing the intensity of therapy to suppress resistant subpopulations; developing concepts of clinical breakpoints to include issues surrounding suppression of resistance; and paying attention to the duration of therapy, which is another important issue for resistance suppression. New understanding of optimizing combination therapy is of interest for difficult-to-treat pathogens likePseudomonas aeruginosa,Acinetobacterspp., and multidrug-resistant (MDR)Enterobacteriaceae. These lessons need to be applied to our old drugs as well to preserve them and to be put into national and international antibiotic resistance strategies. As importantly, from a regulatory perspective, new chemical entities should have a resistance suppression plan at the time of regulatory review. In this way, we can make the best of our current situation and improve future prospects.


2015 ◽  
Vol 59 (5) ◽  
pp. 2835-2841 ◽  
Author(s):  
Qinghua Zhang ◽  
Yanzhao Xu ◽  
Qing Wang ◽  
Bolin Hang ◽  
Yawei Sun ◽  
...  

ABSTRACTWith the emergence of many antibiotic-resistant strains worldwide, antimicrobial peptides (AMPs) are being evaluated as promising alternatives to conventional antibiotics. P3, a novel hemoglobin peptide derived from bovine erythrocytes, exhibited modest antimicrobial activityin vitro. We evaluated the antimicrobial activities of P3 and an analog, JH-3, bothin vitroandin vivo. The MICs of P3 and JH-3 ranged from 3.125 μg/ml to 50 μg/ml when a wide spectrum of bacteria was tested, including multidrug-resistant strains. P3 killed bacteria within 30 min by disrupting the bacterial cytoplasmic membrane and disturbing the intracellular calcium balance. Circular dichroism (CD) spectrometry showed that P3 assumed an α-helical conformation in bacterial lipid membranes, which was indispensable for antimicrobial activity. Importantly, the 50% lethal dose (LD50) of JH-3 was 180 mg/kg of mouse body weight after intraperitoneal (i.p.) injection, and no death was observed at any dose up to 240 mg/kg body weight following subcutaneous (s.c.) injection. Furthermore, JH-3 significantly decreased the bacterial count and rescued infected mice in a model of mouse bacteremia. In conclusion, P3 and an analog exhibited potent antimicrobial activities and relatively low toxicities in a mouse model, indicating that they may be useful for treating infections caused by drug-resistant bacteria.


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