scholarly journals Isolation and Identification of Antibiotic-Producing Halophilic Bacteria from Dagh Biarjmand and Haj Aligholi Salt Deserts, Iran

2019 ◽  
Vol 25 (1) ◽  
pp. 70-77 ◽  
Author(s):  
Babak Elyasifar ◽  
Sevda Jafari ◽  
Somayeh Hallaj-Nezhadi ◽  
Florence Chapeland-leclerc ◽  
Gwenaël Ruprich-Robert ◽  
...  

Background: Halophilic bacteria are potent organisms in production of novel bioactive antimicrobial compounds which might be considered in drug innovation and control of plant pathogens. Salt deserts in Semnan province are of the most permanent hypersaline areas in the North of Iran. Despite the importance of these areas, there is no scientific report regarding the biodiversity and potency of their halophilic bacteria. Thus, aforementioned areas were selected to detect the halophilic bacteria. Methods: Here, seven strains were isolated and cultured on their molecular and biochemical properties were characterized. To determine the antibiotic potency of the isolates, agar well diffusion method was conducted. Phylogenetic analysis was done to reveal the isolates relationship with previously known strains. Results: As a result, growth of the strains in the medium containing 5 to 20% (w/v) NaCl determined that the majority of the isolates were moderately halophile. Catalase activity of all strains was positive. The results represented that D6A, Dar and D8B have antimicrobial effects against different plant and human pathogens. Phylogenic tree analysis also showed that two strains of D6A and Dar are belonged to Bacillus subtilis and D8B is belonged to Virgibacillus olivae. The bacteria extracts were evaluated for their antifungal and antibacterial activities on human and Plant pathogenic strains. The MIC of the extract B. subtilis against was found active against human pathogenic fungi and Plant pathogenic bacteria and fungi, ranging from 12.5 to 25 µg/mL. Conclusion: This study highlights the therapeutic and prophylactic potential of B. subtilis extracts as antibacterial and antifungal agents.

2015 ◽  
Vol 13 (1) ◽  
pp. 97-103 ◽  
Author(s):  
Mohammad Shahnoor Hossain ◽  
Yead Morshed Nibir ◽  
Sayma Zerin ◽  
Nazmul Ahsan

The goal of the present study was to evaluate the antibacterial activity of the methanolic extract of Bangladeshi black tea against various important pathogenic bacteria. Antibacterial activity test was carried out by agar well-diffusion method. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were evaluated using microdilution methods. Extract of Bangladeshi black tea demonstrated potential antibacterial activity in a dose dependent manner against all of the tested bacteria and exhibited highest activity against two common enteric pathogens, Shigella boydii and Vibrio cholerae with MIC and MBC of 200 ?g/ml and 1 mg/ml respectively. Our results indicate that black tea extract can be used as therapeutic to control these deadly pathogens. DOI: http://dx.doi.org/10.3329/dujps.v13i1.21873 Dhaka Univ. J. Pharm. Sci. 13(1): 97-103, 2014 (June)


Author(s):  
Selvarani Murugan

Objective: Resistance to antibacterial agents by pathogenic bacteria has emerged in recent years and is a major challenge for the healthcare industry. Copper nanoparticles (CuNPs) are known to be one of the multifunctional inorganic nanoparticles with effective antibacterial activity. Hence the present investigation has been focused on synthesizing and evaluating the bactericidal effect of copper nanoparticles.Methods: CuNPs were synthesized by reducing the aqueous solution of copper sulfate with sodium borohydride. The synthesized particles were characterized by x-ray diffractogram (XRD), scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) techniques to analyze size, morphology and quantitative information respectively. The antibacterial activity of CuNPs was examined by agar well diffusion method. Synergistic effect of CuNPs with broad-spectrum antibiotics was determined by the agar disc diffusion method.Results: Color change of reaction mixture from blue to dark brown indicated the formation of CuNPs. SEM image clearly demonstrated that the synthesized particles were spherical in shape and its size was found to be 17.85 nm. EDS report confirmed the presence of elemental copper in the resultant nanoparticles and its accounts for major proportion (96%) of the mass of nanoparticles. Bacterial effect of CuNPs revealed that Pseudomonas aeruginosa showed the highest antibacterial sensitivity (16.00±1.63 mm), whereas least susceptibility (9.67±0.47 mm) was noticed against Staphylococcus aureus. An enhanced antibacterial activity of commercial antibiotics was also noticed when it combined with CuNPS. A minimum zone of inhibition was increased from 0.67±0.47 mm to 10.66±0.24 mm when the nanoparticles and antibiotics were given together.Conclusion: It was observed that copper nanoparticles exhibited profound activity against all the tested bacterial strains which shows that CuNPs may serve as a better option for use in medicine in the future.


2010 ◽  
Vol 7 (1) ◽  
pp. 88-92 ◽  
Author(s):  
Pipin T. Kurniawati ◽  
H. Soetjipto ◽  
Leenawati Limantara

Research on Bixa orellana L. have been done to isolate, identify and determine bixin percentage, the antioxidant and antibacterial activities of bixin from B. orellana seed.  Isolation and identification of bixin was done by thin layer chromatography (TLC), column chromatography, chemical test of bixin and UV-Vis double beam spectroscopy. Percentage of bixin was calculated by JECFA method, the antioxidant activity was determined by DPPH (1-1 diphynilpicrylhidrazil) method while antibacterial activity was analyzed by the use of agar diffusion method. Thin layer chromatography (TLC) for the crude extract contained 5 spot, where spot 5th was bixin. Bixa orellana has 75±3% of bixin. Antioxidant activity of bixin had IC50 548.5±20.0 ppm. Whereas the antibacterial activity of bixin against the Escherichia coli and Staphylococus aureus could be classified as weak inhibition category at 500-750 μg and medium inhibition category at 1500 μg.   Keywords: Bixa orellana L., bixin, antioxidant, antibacteria


Author(s):  
Mohammed M Matin ◽  
Mohammad Ibrahim ◽  
Md Shafiqur Rahman

A number of 2,3-di-O-acyl derivatives (6-11) of methyl 4-O-acetyl-a-Lrhamnopyranoside (5) obtained by using various acylating agents were screened for in vitro antifungal activity against four plant pathogenic fungi, viz., Alternaria alternata, Curvularia lunata. Fusarium equiseti and Macrophomina phaseolina. These compounds were also screened for in vitro antibacterial activity against ten human pathogenic bacteria, viz., Bacillus subtilis, Bacillus cereus, Bacillus megaterium, Staphylococcus aureus, Escherichia coli, INABA ET (Vibrio), Pseudomonas species, Salmonella paratyphi, Shigella dysenteriae and Salmonella typhi. The study reveal that these 4-O-acetyl-?-L-rhamnopyranoside derivatives are more prone towards antifungal activities than that of antibacterial activities. DOI: http://dx.doi.org/10.3329/cujbs.v3i1.13404 The Chittagong Univ. J. B. Sci.,Vol. 3(1&2):33-43, 2008


Pathogens ◽  
2020 ◽  
Vol 9 (6) ◽  
pp. 420 ◽  
Author(s):  
Mst. Sonia Parvin ◽  
Sudipta Talukder ◽  
Md. Yamin Ali ◽  
Emdadul Haque Chowdhury ◽  
Md. Tanvir Rahman ◽  
...  

Escherichia coli is known as one of the most important foodborne pathogens in humans, and contaminated chicken meat is an important source of foodborne infection with this bacterium. The occurrence of extended-spectrum β-lactamase (ESBL)-producing E. coli (ESBL-Ec), in particular, in chicken meat is considered a global health problem. This study aimed to determine the magnitude of E. coli, with special emphasis on ESBL-Ec, along with their phenotypic antimicrobial resistance pattern in frozen chicken meat. The study also focused on the determination of ESBL-encoding genes in E. coli. A total of 113 frozen chicken meat samples were purchased from 40 outlets of nine branded supershops in five megacities in Bangladesh. Isolation and identification of E. coli were done based on cultural and biochemical properties, as well as PCR assay. The resistance pattern was determined by the disc diffusion method. ESBL-encoding genes were determined by multiplex PCR. The results showed that 76.1% of samples were positive for E. coli, of which 86% were ESBL producers. All the isolates were multidrug-resistant (MDR). Resistance to 9–11 and 12–13 antimicrobial classes was observed in 38.4% and 17.4% isolates, respectively, while only 11.6% were resistant to 3–5 classes. Possible extensive drug resistance (pXDR) was found in 2.3% of isolates. High single resistance was observed for oxytetracycline (93%) and amoxicillin (91.9%), followed by ampicillin (89.5%), trimethoprim–sulfamethoxazole, and pefloxacin (88.4%), and tetracycline (84.9%). Most importantly, 89.6% of isolates were resistant to carbapenems. All the isolates were positive for the blaTEM gene. However, the blaSHV and blaCTX-M-2 genes were identified in two ESBL-non producer isolates. None of the isolates carried the blaCTX-M-1 gene. This study provided evidence of the existence of MDR and pXDR ESBL-Ec in frozen chicken meat in Bangladesh, which may pose a risk to human health if the meat is not properly cooked or pickled raw only. This emphasizes the importance of the implementation of good slaughtering and processing practices by the processors.


2018 ◽  
Vol 29 ◽  
pp. 70-77 ◽  
Author(s):  
Anjana Devkota ◽  
Ritu Kumari Das

Antibacterial activities of Xanthium strumarium L. (Asteraceae) was carried out in laboratory. Distilled water and methanol extracts of the leaves of plant was prepared. The antibacterial activity was studied against six pathogenic bacteria, three gram negative: Klebsiella pneumoniae (ATCC 15380), Proteus mirabilis (ATCC 49132), Escherichia coli (ATCC 25922) and three gram positive: Bacillus subtilis (ATCC 6633), Enterococcus faecalis (ATCC 29212), Staphylococcus aureus (ATCC 25932) at different concentrations (50 mg/ml, 100 mg/ml, 150 mg/ml, 200 mg/ ml, 250 mg/ml) of leaf extracts of X. strumurium. The phytochemical screening depicted the presence of terpenoids, saponins, flavonoids, tannins and alkaloids. The antibacterial activity of extracts was determined by disc diffusion method and zone of inhibition (ZOI) was measured. Gram negative bacteria was found more resistant than gram positive bacteria. The most susceptible bacterium was S. aureus while the most resistant bacterium was E. coli. Methanolic extract was found more effective than distilled water. These findings suggest that extracts obtained from leaves of X. strumurium possess biobactericidal potential, which can suitably be exploited for making antibacterial drugs.J. Nat. Hist. Mus. Vol. 29, 2015, Page: 70-77


2016 ◽  
Vol 8 (2) ◽  
pp. 209-216
Author(s):  
A. Rahim ◽  
R. Ali ◽  
A. Islam

 2',4',5'- and 2',3',4'-trimethoxy flavanones have been synthesized starting with 2-hydroxyacetophone and substituted aldehyde. Antibacterial activities of the flavanones have been tested along with their corresponding chalcones against two human pathogenic bacteria (Streptococcus-b-haemolyticus and  Klebsiella sp. (G-)). Antifungal activities of the flavanones have also been investigated against  two plants pathogenic mold fungi (Rhizactonia solani Sclerotium rolfsii). The structures of the synthesized compounds have been characterized with the help of  UV, IR and 1H NMR and 13C-NMR spectra. The antibacterial and antifungal screening were performed in vitro by the filter paper disc diffusion method and poisoned food technique. The flavanones showed antibacterial activity while no activity was observed to their corresponding chalcones against the tested bacteria. On the other hand, chalcones and their corresponding flavanones both showed fungicidal activities.


2020 ◽  
Vol 17 (7) ◽  
pp. 631-638
Author(s):  
Dele ABDISSA ◽  
Gezahegn FAYE ◽  
Melkamu FAYERA ◽  
Shiferaw DEMISSIE

Kniphofia pumila has been traditionally used for the treatment of different diseases in Oromiya regional state, western part of Ethiopia. Thus, the main objective of this study was to extract bioactive natural products from the roots of K. pumila and perform in vitro antibacterial activity tests against selected pathogens. Extraction of compound from the roots of K. pumila was carried out by maceration method at room temperature and its antibacterial activity was done using agar disc diffusion method. The crude extracts alone and along with ZnCl2 were tested against pathogenic bacteria Escherichia coli (ATCC 25722), Klebsiella pneumoniae subsp. pneumoniae (DSM 19613), Staphylococcus aureus (ATCC 25925) and Salmonella Typhimurium (ATCC 13311). Following its promising activity, the acetone crude extract that have shown better antibacterial activity was subjected to column chromatography for isolation of pure compound. Hence, one pure compound (GZ-1) was obtained from acetone crude extract. Meanwhile, the antibacterial activities of the isolated compound alone and in combination with ZnCl2 were also performed against all aforementioned bacterial strains. Then, isolated compound was characterized by using NMR spectroscopic techniques such as 1H-NMR, 13C-NMR and, 2D NMR, so as to establish its structure as 3’-acetyl-2’,6’-dihydroxy-4-methoxyphenyl-1,8-dihydroxy-3-methylanthraquinone, trivial name knipholone. Finally, GZ-1 was isolated from the roots of K. pumila and it was noted that the antibacterial activities of ZnCl2 in combination with crude extract as well as with isolated compound against E. coli (ATCC 25722), S. aureus (ATCC 25925) and S. Typhimurium (ATCC 13311) bacterial strains showed remarkable results which were greater than the antibacterial activity of the positive standard drug (gentamycin). To sum up, from the chromatographic isolation of roots acetone extract of K. pumila one pure compound (knipholone) was obtained. Its antibacterial activity was also evaluated in combination with ZnCl2 salt and alone.


2021 ◽  
Vol 22 (5) ◽  
Author(s):  
Elnaz Ahmadnejad ◽  
Samaneh Dolatabadi

Background: Probiotic bacteria are one of the useful dietary supplements for human health. The main reason for selecting probiotics is the lack of prolonged side effects. Objectives: This study aimed to isolate lactobacilli from traditional yogurt and cheese samples collected in Neyshabur city, Khorasan Razavi, Iran, and to characterize them using specific biochemical and molecular assays. Methods: The probiotic potency of bacteria was tested by resistance to acid, bile, NaCl, and organic acid production. Moreover, the antagonistic effects of the isolates were investigated against enteric pathogenic bacteria using the well diffusion method. Bacteriocin production was also investigated using the microtiter plate assay. Results: Four Lactobacillus spp. with > 99% homology to L. reuteri, L. plantarum, and L. acidophilus, were isolated with probiotic potency. The quantitative measurements used in the study with the statistical analysis resulted in the interpretation of good effects against Clostridium perfringens, Salmonella typhi, Staphylococcus aureus, and Listeria monocytogenes. Our isolates exhibited bile salt hydrolase activity, excellent NaCl and acid tolerance (pH = 3), and bacteriocin production. Conclusions: Our results showed that Lactobacillus strains isolated from Neyshabur traditional cheese could be considered good potential probiotic strains and had more antagonistic activity against human pathogens when compared to other samples. Their antibacterial activity was associated with both bacteriocin and organic acids production, but they should be further investigated for their human health benefits.


2021 ◽  
Vol 5 (1) ◽  
pp. 436-444
Author(s):  
Sabiu Shitu ◽  
M. Attahiru ◽  
F. A. Iliya

The antibacterial activity of Tokar sha; a local traditional medication widely used by many people in North-west zone of Nigeria especially Sokoto, Kebbi and Zamfara against enteric infections were examined against some clinical isolates of pathogenic bacteria (Staphylococcus aureus, Escherichia coli, Bacillus cereus and Salmonella typhi) using agar well diffusion method. The pattern of inhibition varied with the tokar sha concentrations and the organisms tested. The tokar sha was more effective on E. coli with a maximum zone of growth inhibition of 25mm at 35mg/ml followed by B. cereus (20mm). However, S. aureus and S. typhi were resistant to tokar sha at all concentrations tested. The minimum inhibitory concentrations (MIC) were found to be 35mg/ml for both E. coli and B. cereus. The antibacterial activities exhibited by tokar sha in this study could be attributed to the presence of its constituents which signifies the potential of the tokar sha as a therapeutic agent. These findings may justify the ethnomedicinal use of tokar sha as an antibacterial agent against enterobacteria


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