scholarly journals Bacteriocin-mediated inhibition of some common pathogens by wild and mutant Lactobacillus species and in vitro amplification of bacteriocin encoding genes

ADMET & DMPK ◽  
2021 ◽  
Author(s):  
Arooj Ahsan ◽  
Bushra Mazhar ◽  
Muhammad Kamran Khan ◽  
Madiha Mustafa ◽  
Muhammad Hammad ◽  
...  
Keyword(s):  
Gene Sequence ◽  
Diffusion Method ◽  
Lactobacillus Species ◽  
Lactobacillus Curvatus ◽  
Biochemical Tests ◽  
Specific Primers ◽  
Gram Staining ◽  
Salmonella Enteritis ◽  
Encoding Genes

Lactobacilli are the most common probiotics used in food and other industries because of their capability of producing bacteriocins. Bacteriocins are compounds that are used to kill pathogenic microorganisms. As most bacteria have become resistant to synthetic antibacterial tools, the importance of using probiotics as antibacterial agents has increased. This work was done to check the bacteriocin effect on some common pathogens and the influence of mutation on the bacteriocin activity of Lactobacilli was also investigated. Four strains were isolated, identified from meat and pickles samples via culturing methods, staining, biochemical tests, and ribotyping. Preliminary tests, including Gram staining and catalase test, were done for the confirmation of Lactobacillus species. All strains were gram-positive and catalase-negative. Antibacterial activity was checked against Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus thuringiensis, Escherichia coli, and Salmonella enteritis via agar well diffusion method. The mutations were done using ethidium bromide and the influence of wild and mutants were also checked. Interestingly, mutants developed more virulence than wild ones. It was also observed that they all were sensitive to pepsin. Protein estimation was done via Bradford method. Ribotyping of GCU-W-PS1 revealed 99 % homology with Lactobacillus plantarum and GCU-W-MS1 to Lactobacillus curvatus (99 % homology). Curvacin A, sakacin P, and plantaricin A genes were also amplified using specific primers. Gene sequence showed the presence of curvacin A gene in GCU-W-MS1. It was concluded that lactic acid bacteria could be used as antibacterial tools against common pathogens.

scholarly journals Isolation of Lactobacillus species from fermented Parkia biglobosa seed and screening for their probiotic activity

2021 ◽  
Vol 13 (Volume 13, Issue 2) ◽  
pp. 212-216
Author(s):  
K. Kuti ◽  
I.M. Hussaini ◽  
A. Usman ◽  
A. Isa
Keyword(s):  
Antibacterial Activity ◽  
Low Ph ◽  
Lactobacillus Species ◽  
Biochemical Tests ◽  
Antimicrobial Substances ◽  
Probiotic Potential ◽  
Gram Staining ◽  
Colonial Morphology ◽  
Lactobacillus Spp

Abstract. Food fermentation has been a tradition for decades due to its immense benefits. Lactic acid bacteria are known to possess probiotic potential due to various chemical antimicrobial substances they produce. This research was aimed at isolating Lactobacillus spp. from locally fermented locust beans and screening the isolates for their probiotic potential. A total of 20 samples of fermented locust beans (P. biglobosa) were collected and processed. The samples were inoculated onto de-Mann Rogosa Sharpe (MRS) media and incubated anaerobically. The isolates with characteristic colonial morphology of Lactobacillus sp. were characterized using Gram staining and biochemical tests. Lactobacillus spp. isolates were screened in-vitro for probiotic potential using the following parameters, tolerance of low pH, bile tolerance and antimicrobial activity. Four isolates of Lactobacillus species consisting of Lactobacillus fermentum and Lactobacillus plantarum were isolated from different fermented locust beans. All isolates showed tolerance to low pH and bile concentration of 3.04 and 0.3%, respectively. The Lactobacillus species isolates showed varying antibacterial activity against all test bacteria with isolate S06 (L. plantarum) showing the highest degree of antibacterial activity. In conclusion, the Lactobacillus species isolated from fermented locust beans can serve as probiotic candidate.

scholarly journals Antibiotic sensitivity and in vitro antimicrobial activity of plant extracts to pseudomonas fluorescens isolates collected from diseased fish

1970 ◽  
Vol 1 (4) ◽  
pp. 82-88 ◽  
Author(s):  
MJ Foysal ◽  
MM Rahman ◽  
M Alam
Keyword(s):  
Antibacterial Activity ◽  
Pseudomonas Fluorescens ◽  
Plant Extracts ◽  
Antibiotic Sensitivity ◽  
Diffusion Method ◽  
Biochemical Tests ◽  
Leaf Extracts ◽  
Sensitivity Pattern ◽  
Medicinal Plant Extracts

Studies were conducted to identify Pseudomonas fluorescens isolates from a collection of bacteria isolated from bacterial haemorrhagic septicaemia infected carp and catfish, evaluate their antibiotic sensitivity pattern and screen the antibacterial activity of some medicinal plant extracts against the isolates.. A total of 10 isolates were identified as P. fluorescens by morphological, physiological and biochemical tests. In vitro antibiotic sensitivity test of the P. fluorescens isolates were conducted by disc diffusion method for seven antibiotics where, all of the isolates were found to be sensitive only against streptomycin and gentamycin but, most of the isolates (80%) were found resistant to chloramphenicol (C). Moreover, eighty percent of the isolates showed resistance to multiple antibiotics. A total of 118 plant extracts were screened for their antibacterial activity against the P. fluorescens isolates where the isolates exhibited sensitivity to 30 samples. Leaf extracts of Tamarindus indicus, Terminalia chebula, Citrus aurantifolia, Eugenia caryophyllata and Spondias pinnata were found to inhibit the growth of all of the P. fluorescens isolates. DOI: http://dx.doi.org/10.3329/ijns.v1i4.9733 IJNS 2011 1(4): 82-88

scholarly journals Effect of blue laser on viability of Proteus mirabilis

2021 ◽  
pp. 1438-1446
Author(s):  
Mawada M. Funjan
Keyword(s):  
Exposure Time ◽  
Proteus Mirabilis ◽  
Bacterial Species ◽  
Test System ◽  
Blue Laser ◽  
Diffusion Method ◽  
Biochemical Tests ◽  
Burn Wounds ◽  
Antibiotic Susceptibility Test

The usage of blue laser has been considered as a therapeutic approach to prohibit the viability of bacterial species, but there is no agreement about optimum parameters to be used. The aim of this project is to study the influence of blue laser (450 nm) on the viability of the gram-negative bacteria  Proteus mirabilis isolated from burn wounds, using different exposure times (i.e. doses) in vitro. Seventy swab samples were collected from burn wounds of patients admitted to the burns unit in AL-Yarmouk teaching hospital in Baghdad, during the period from June to August 2019. The Bacteria were isolated and identified depending on their culture characteristics, biochemical tests, gram staining, and morphology, being finally confirmed by API 20E Test System. By using the disk diffusion method, susceptibility of the isolates to 12 different antibiotics was examined. One isolate of P. mirabilis was elected according to susceptibility to all antibiotics used.  To prepare bacterial solution, P. mirabilis was mixed with normal saline solution. Dilution of 10-6 cell/ml for p. mirabilis was selected from other serial dilutions. A number of colonies and colony forming units (CFUs/ml) were achieved and correlated to controls.  P. mirabilis was irradiated by blue diode laser (450 nm, 500mw) and exposed to different doses (24, 48, 72, 96, 120J/cm2) corresponding to respective exposure times (4, 8,12,16,20 minutes). The results of antibiotic susceptibility test indicate that the entire isolates of P. mirabilis were multidrug resistant. With the increase in laser dose (exposure times), the number of colonies and  CFUs/ml were reduced, reaching a highest inhibition in CFU/ml  at exposure time of  20 minutes, i.e. a dose of 120J/cm2 , with  irradiance of 0.1 watt/ cm2. No significant reduction was recorded in CFU/ml   at exposure time of 4 min (a dose of 24J/cm2). As a conclusion, the blue laser irradiation at wavelength of 450 nm and 500mw had antibacterial effects on P. mirabilis isolated from burn wounds with irradiance of 0.1watt/cm2 in vitro, as evidenced by the effective reduction in the viability of bacteria at a dose of 120J/cm2 corresponding to exposure time of 20 minutes.

Bacillus thermotolerans sp. nov., a thermophilic bacterium capable of reducing humus

2013 ◽  
Vol 63 (Pt_10) ◽  
pp. 3672-3678 ◽  
Author(s):  
Guiqin Yang ◽  
Xuemei Zhou ◽  
Shungui Zhou ◽  
Dehui Yang ◽  
Yueqiang Wang ◽  
...  
Keyword(s):  
Gene Sequence ◽  
Cellular Fatty Acid ◽  
Thermophilic Bacterium ◽  
Anaerobic Growth ◽  
Rrna Gene ◽  
Biochemical Tests ◽  
Unidentified Phospholipid ◽  
Content Type ◽  
Link Type ◽  
Gram Staining

A novel thermotolerant bacterium, designated SgZ-8T, was isolated from a compost sample. Cells were non-motile, endospore-forming, Gram-staining positive, oxidase-negative and catalase-positive. The isolate was able to grow at 20–65 °C (optimum 50 °C) and pH 6.0–9.0 (optimum 6.5–7.0), and tolerate up to 9.0 % NaCl (w/v) under aerobic conditions. Anaerobic growth occurred with anthraquinone-2,6-disulphonate (AQDS), fumarate and NO3 - as electron acceptors. Phylogenetic analysis based on the16S rRNA and gyrB genes grouped strain SgZ-8T into the genus Bacillus , with the highest similarity to Bacillus badius JCM 12228T (96.2 % for 16S rRNA gene sequence and 83.5 % for gyrB gene sequence) among all recognized species in the genus Bacillus . The G+C content of the genomic DNA was 49.3 mol%. The major isoprenoid quinone was menaquinone 7 (MK-7) and the polar lipids consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and an unidentified phospholipid. The major cellular fatty acid was iso-C16 : 0. On the basis of its phenotypic and phylogenetic properties, chemotaxonomic analysis and the results of physiological and biochemical tests, strain SgZ-8T ( = CCTCC AB 2012108T = KACC 16706T) was designated the type strain of a novel species of the genus Bacillus , for which the name Bacillus thermotolerans sp. nov. is proposed.

Terrabacter terrae sp. nov., a novel actinomycete isolated from soil in Spain

2005 ◽  
Vol 55 (6) ◽  
pp. 2491-2495 ◽  
Author(s):  
Marta Montero-Barrientos ◽  
Raúl Rivas ◽  
Encarna Velázquez ◽  
Enrique Monte ◽  
Manuel G. Roig
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Gene Sequence ◽  
Sequence Similarity ◽  
16S Rrna Gene Sequence ◽  
Rrna Gene ◽  
Rrna Gene Sequence ◽  
Biochemical Tests ◽  
Bacterium Strain

A Gram-positive, aerobic, long-rod-shaped, non-spore-forming bacterium (strain PPLBT) was isolated from soil mixed with Iberian pig hair. This actinomycete showed keratinase activity in vitro when chicken feathers were added to the culture medium. Strain PPLBT was oxidase-negative and catalase-positive and produced lipase and esterase lipase. This actinomycete grew at 40 °C on nutrient agar and in the same medium containing 5 % (w/v) NaCl. Growth was observed with many different carbohydrates as the sole carbon source. On the basis of 16S rRNA gene sequence similarity, strain PPLBT was shown to belong to the genus Terrabacter of the family Intrasporangiaceae. Strain PPLBT showed 98·8 % 16S rRNA gene sequence similarity to Terrabacter tumescens. Chemotaxonomic data, such as the main ubiquinone (MK-8), the main polar lipids (phosphatidylethanolamine, diphosphatidylglycerol and phosphatidylinositol) and the main fatty acids (i-C15 : 0, ai-C15 : 0, i-C16 : 0 and ai-C17 : 0) supported the affiliation of strain PPLBT to the genus Terrabacter. The G+C content of the DNA was 71 mol%. The results of DNA–DNA hybridization (36·6 % relatedness between Terrabacter tumescens and strain PPLBT) and physiological and biochemical tests suggested that strain PPLBT belongs to a novel species of the genus Terrabacter, for which the name Terrabacter terrae sp. nov. is proposed. The type strain is PPLBT (=CECT 3379T=LMG 22921T).

Taibaiella koreensis sp. nov., isolated from soil of a ginseng field

2014 ◽  
Vol 64 (Pt_3) ◽  
pp. 1018-1023 ◽  
Author(s):  
Heung-Min Son ◽  
MooChang Kook ◽  
Ju-Han Kim ◽  
Tae-Hoo Yi
Keyword(s):  
Gene Sequence ◽  
Sequence Similarity ◽  
Rrna Gene ◽  
Strictly Aerobic ◽  
The Novel ◽  
Biochemical Tests ◽  
Phenotypic Data ◽  
Link Type ◽  
Gram Staining ◽  
The Republic

A Gram-staining-negative, strictly aerobic, motile (by gliding), non-spore-forming and rod-shaped bacterial strain, designated THG-DT86T, was isolated from soil of a ginseng field of Pocheon province in the Republic of Korea and its taxonomic position was investigated by a polyphasic approach. Growth occurred at 10–35 °C, at pH 6.5–8.5 and with 0–1.5 % (w/v) NaCl on trypticase soy agar. Flexirubin-type pigments were found to be present. On the basis of 16S rRNA gene sequence similarity, strain THG-DT86T was shown to belong to the genus Taibaiella and was related to Taibaiella smilacinae PTJT-5T (95.3 %). The G+C content of the genomic DNA was 50.1 mol%. The only isoprenoid quinone detected in strain THG-DT86T was menaquinone-7 (MK-7) and the only polyamine was homospermidine. The predominant fatty acids were iso-C15 : 0, iso-C17 : 0 3-OH, C16 : 0, iso-C15 : 1 G and iso-C17 : 0, and the major polar lipids were phosphatidylethanolamine, an unidentified aminophosphoglycolipid and an unidentified aminophospholipid. Phenotypic data and phylogenetic inference supported the affiliation of strain THG-DT86T to the genus Taibaiella , and a number of biochemical tests differentiated strain THG-DT86T from the recognized species of the genus Taibaiella . Therefore, the novel isolate represents a novel species, for which the name Taibaiella koreensis sp. nov. is proposed, with THG-DT86T as the type strain ( = KACC 17171T = JCM 18823T).

scholarly journals <i>In-vitro</i> antibacterial sensitivity of <i>Usnea barbata</i> lichen extracted with methanol and ethyl-acetate against selected <i>Staphylococcus</i> species from milk of cows with mastitis

2014 ◽  
Vol 57 (1) ◽  
pp. 1-9 ◽  
Author(s):  
Emrobowansan Monday Idamokoro ◽  
Patrick Julius Masika ◽  
Voster Muchenje ◽  
Daniel Falta ◽  
Ezekiel Green
Keyword(s):  
Antimicrobial Activity ◽  
Medicinal Plant ◽  
Ethyl Acetate ◽  
Ethyl Acetate Extract ◽  
Bovine Milk ◽  
Raw Milk ◽  
Diffusion Method ◽  
Biochemical Tests ◽  
Ethyl Acetate Extracts

Abstract. This study aimed at evaluating the antimicrobial potential of Usnea barbata lichen as a medicinal plant against selected Staphylococcus species isolated from raw milk of cows. In-vitro screening of methanol and ethyl-acetate extracts from Usnea barbata lichen were evaluated to determine their antimicrobial activity against thirteen different Staphylococcus species. The selected organisms were isolated from raw bovine milk and identified using several biochemical tests and confirmed with API staph kit. The antimicrobial activity of the extracts were evaluated using both the agar well diffusion method (at 5 mg/ml, 10 mg/ml and 20 mg/ml) and the broth micro-dilution technique to determine the mean zone of inhibition and the minimum inhibitory concentration (MIC), respectively. Both the methanol and ethyl-acetate extracts showed variable antimicrobial activity against the Staphylococcus species with mean zones of inhibition ranging from 0-34 mm in diameter at 5 mg/ml, 10 mg/ml and 20 mg/ml, respectively. Susceptibility by the Staphylococcus species tested in the methanol and the ethyl-acetate extract was 92.31 % and 53.85 %, respectively. The MIC result for the methanol extract ranged from 0.04 to 10 mg/ml, while that of the ethyl-acetate extract ranged from 0.16 to 5 mg/ml. Results from this study revealed the in vitro microbial activity of Usnea barbata extracts which indicate its potential as a medicinal plant.

HISTOLOGICAL STUDY OF LETTUCE AND BASIL BY INFECTION WITH PS. AERUGINOSA AND PS. FLUORESCENS IN VITRO

2020 ◽  
pp. 56-69
Author(s):  
G.V. GODOVA ◽  
◽  
A.A. OVOD ◽  
N.V. ASTAKHOVA ◽  
E.A. KALASHNIKOVA ◽  
...  
Keyword(s):  
Virulent Strain ◽  
Histological Study ◽  
Plant Cells ◽  
Ultrastructural Changes ◽  
Cytotoxic Action ◽  
Biochemical Tests ◽  
Potential Threat ◽  
Gram Staining ◽  
Electronic Microscope

Studies based on the use of an electronic microscope revealed ultrastructural changes in plant cells of lettuce and Basil in interaction with Ps.aeruginosa ATCC B3994, expressed in deformation and violation of the integrity of the cell wall, increasing the size of chloroplasts, sometimes full destruction accompanied by the increased number of plastoglobuli. Ps.fluorescens ATСC948 were localized in the cytoplasm and chloroplasts of cells without a cytotoxic action. Plant isolates were identified with gram staining, biochemical tests and PCR. Contamination of non-heattreated leaf vegetables with virulent strain Ps. aeruginosa is a potential threat to human health and life.

scholarly journals Pedobacter glucosidilyticus sp. nov., isolated from dry riverbed soil

2010 ◽  
Vol 60 (1) ◽  
pp. 229-233 ◽  
Author(s):  
Xuesong Luo ◽  
Zhang Wang ◽  
Jun Dai ◽  
Lei Zhang ◽  
Jun Li ◽  
...  
Keyword(s):  
Gene Sequence ◽  
Sequence Similarity ◽  
Rrna Gene ◽  
The Novel ◽  
Bacterial Strains ◽  
Biochemical Tests ◽  
Respiratory Quinone ◽  
Gram Staining ◽  
Major Respiratory Quinone ◽  
Physiological And Biochemical

Two Gram-staining-negative, rod-shaped, non-spore-forming bacterial strains, 1-2T and 1-4 were isolated from dry riverbed soil collected from the Xietongmen area of Tibet, China. On the basis of 16S rRNA gene sequence similarity, the novel strains were shown to belong to the genus Pedobacter, sharing <95 % sequence similarity with all recognized species of the genus Pedobacter. The major respiratory quinone was MK-7 and the predominant cellular fatty acids were iso-C15 : 0, iso-C17 : 0 3-OH and summed feature 3 (comprising iso-C16 : 1 ω7c and/or C16 : 1 ω6c). The DNA G+C contents were 37.2–37.6 mol%. Chemotaxonomic data supported the affiliation of the two new isolates to the genus Pedobacter and the results of physiological and biochemical tests confirmed that the new strains differed significantly from the recognized species of the genus Pedobacter. Therefore, the new isolates represent a novel species within the genus Pedobacter, for which the name Pedobacter glucosidilyticus sp. nov. is proposed. The type strain is 1-2T (=CCTCC AB 206110T=KCTC 22438T).

scholarly journals ISOLASI DAN UJI AKTIVITAS ANTIBAKTERI DARI BAKTERI YANG BERASOSIASI DENGAN ALGA Turbinaria ornata (Turner) J. Agardh SERTA IDENTIFIKASI SECARA BIOKIMIA

PHARMACON ◽  
2019 ◽  
Vol 8 (2) ◽  
pp. 351
Author(s):  
Cicilia Kosasi ◽  
Widya A. Lolo ◽  
Sri Sudewi
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Antibacterial Activity ◽  
Diffusion Method ◽  
Genus Bacillus ◽  
Biochemical Tests ◽  
Isolation And Purification ◽  
Turbinaria Ornata ◽  
Gram Staining ◽  
Escherichia Coli Bacteria

ABSTRACT Algae are a place to live for various microorganisms’ symbiosis with them, and some of them were known to be used as antibacterial. This study aims to determine the antibacterial activity of associated bacteria isolates from Turbinaria ornata algae obtained from the Bay of Manado against Staphylococcus aureus and Escherichia coli bacteria. In the course of testing the isolation and purification of symbiotic bacteria from Turbinaria ornata algae, then antibacterial activity was testing using agar diffusion method, then gram staining and biochemical tests were carried out including motility test,  tets, carbohydrate fermentation test, citrate test, lysine test, indole test and catalase test. The result showed  that there were 3 bacterial isolates, which had antibacterial activity in medium category against S.aureus and E.coli bacteria. Based on the results of biochemical identification, the isolates that have the greatest inhibitory power, they were thought to belong to genus Bacillus and the genus Yersinia.Keywords : Antibacterial, Symbionic bacteria, Turbinaria ornata (Turner) J.   Agardh. ABSTRAK Alga merupakan tempat hidup berbagai mikroorganisme yang bersimbiosis dengannya, dan beberapa dari spesies alga diketahui sering dimanfaatkan salah satunya  sebagai antibakteri. Penelitian ini bertujuan untuk mengetahui adanya aktivitas antibakteri dari isolat bakteri yang berasosiasi dengan alga Turbinaria ornata yang diperoleh dari Teluk Manado terhadap bakteri  Staphylococcus aureus dan Escherichia coli. Dalam pengujian dilakukan isolasi dan purfifikasi bakteri simbion dari alga Turbinari ornata, kemudian dilakukan pengujian aktivitas antibakteri menggunakan metode difusi agar, selanjutnya silakukan pewarnaan gram dan uji biokimia meliputi uji motilitas, uji H2S, uji fermentasi karbohidrat, uji sitrat, uji lisin, uji indol dan uji katalase. Hasil penelitian menunjukkan bahwa terdapat 3 isolat bakteri yang mempunyai daya aktivitas antibakteri dalam kategori sedang terhadap bakteri S. aureus dan E. coli. Berdasarkan hasil identifikasi secara biokimia isolat yang mempunyai daya hambat paling besar diduga termasuk dalam genus Bacillus dan genus Yersinia. Kata kunci : Antibakteri, Bakteri simbion, Turbinaria ornata (Turner) J. Agardh.

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