scholarly journals First report on antibiotic resistance and antimicrobial activity of bacterial isolates from 13,000-year old cave ice core

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Victoria I. Paun ◽  
Paris Lavin ◽  
Mariana C. Chifiriuc ◽  
Cristina Purcarea
Keyword(s):  
Ice Core ◽  
Great Majority ◽  
Late Glacial ◽  
Bacterial Isolates ◽  
Bacterial Strains ◽  
Gram Positive ◽  
Gram Negative ◽  
Cold Environments ◽  
Cultivable Bacteria ◽  
Perennial Ice

AbstractDespite the unique physiology and metabolic pathways of microbiomes from cold environments providing key evolutionary insights and promising leads for discovering new bioactive compounds, cultivable bacteria entrapped in perennial ice from caves remained a largely unexplored life system. In this context, we obtained and characterized bacterial strains from 13,000-years old ice core of Scarisoara Ice Cave, providing first isolates from perennial ice accumulated in caves since Late Glacial, and first culture-based evidences of bacterial resistome and antimicrobial compounds production. The 68 bacterial isolates belonged to 4 phyla, 34 genera and 56 species, with 17 strains representing putative new taxa. The Gram-negative cave bacteria (Proteobacteria and Bacteroidetes) were more resistant to the great majority of antibiotic classes than the Gram-positive ones (Actinobacteria, Firmicutes). More than 50% of the strains exhibited high resistance to 17 classes of antibiotics. Some of the isolates inhibited the growth of clinically important Gram-positive and Gram-negative resistant strains and revealed metabolic features with applicative potential. The current report on bacterial strains from millennia-old cave ice revealed promising candidates for studying the evolution of environmental resistome and for obtaining new active biomolecules for fighting the antibiotics crisis, and valuable cold-active biocatalysts.

scholarly journals Isolation and Characterization of Bacteria with Biochemical and Pharmacological Importance from Soil Samples of Dhaka City

2017 ◽  
Vol 16 (1) ◽  
pp. 129-136 ◽  
Author(s):  
Kohinur Begum ◽  
Sultana Juhara Mannan ◽  
Refaya Rezwan ◽  
Md Mahinur Rahman ◽  
Md Shajidur Rahman ◽  
...  
Keyword(s):  
Bioactive Compound ◽  
Soil Samples ◽  
Penicillin G ◽  
Dhaka City ◽  
Bacterial Isolates ◽  
Bacterial Strains ◽  
Biochemical Tests ◽  
Gram Positive ◽  
Gram Negative ◽  
Isolation And Characterization

We studied soil samples from Dhaka municipality area to isolate and characterize bacteria having potential biochemical and pharmacological importance. Total twenty five soil samples were collected from fish, vegetables and fruits dump area from Dhaka City. Bacterial population was sub-cultured in trypticase soya agar (TSA) plate. Nineteen colonies were isolated, cultured and characterized by gram staining and biochemical tests. Six isolates were found to be gram negative while thirteen were gram positive. All isolates were positive in oxidase, catalase, citrate, and protease tests. Eight isolates showed coagulase negative and nine were coagulase positive. It was found that all bacterial isolates were sensitive to tetracycline, chloramphenicol, gentamycin, ciprofloxacin, azithromycin and ceftriaxone. About 95% of the bacterial isolates were resistant to penicillin-G and ampicillin. About 89%, 26%, 21% and 11% of the bacterial isolates were resistant to amoxicillin, co-trimoxazole, nalidixic acid and erythromycin, respectively. It was found that bacterial isolates produce chemical(s) inhibitory to other bacterial strains including both gram positive and gram negative bacteria. Further studies are needed to characterize the potential antibacterial factor(s) and other bioactive compound (s) present in these bacterial isolates from soil samples.Dhaka Univ. J. Pharm. Sci. 16(1): 129-136, 2017 (June)

scholarly journals Bacterial status and pollution level in the sediment of Gulshan Lake, Dhaka

2013 ◽  
Vol 38 (2) ◽  
pp. 155-161 ◽  
Author(s):  
Md Abdul Karim ◽  
Nazneen Akhter ◽  
Sirajul Hoque
Keyword(s):  
Bacterial Count ◽  
Pollution Level ◽  
Bacterial Isolates ◽  
Residential Areas ◽  
Bacterial Strains ◽  
Genus Bacillus ◽  
Nitrogen And Phosphorus ◽  
Gram Positive ◽  
Gram Negative ◽  
Different Seasons

Gulshan-Baridhara lake located in and around Gulshan, Banani and Baridhara, has always been Dhaka’s most exclusive residential area mainly because of the pristine lake. The lake is elongated in a north south direction and surrounded mainly by residential areas and some industrial units as well. To evaluate the pollution level of the sediment of the lake, samples were collected from 4 selected locations in 4 different seasons. Four different media were used to study the aerobic heterotrophic, enteric and related bacterial count. Aerobic heterotrophic bacterial count was in the range of 1.1 × 104 to 1.2 ×106 cfu/g in sediment sample, while enteric and related bacterial count in 3 different media (SS agar, MacConkey agar and Cetrimide agar) were 1×100 to 1.5×104 cfu/g, 1×100 to 6×104, and 1×100 to 1.1×103 cfu/g in sediment, respectively. Out of 23 bacterial isolates 18 were Gram-positive and 5 were Gram-negative. Among the Gram-positive, all were rod shaped spore former and under the genus Bacillus. Out of 5 Gram-negative isolates 2 were the member of Pseudomonas, remaining 3 strains were Escherichia, Aeromonas and Enterobacter. Total nitrogen and phosphorus level along with the presence of different bacterial strains clearly indicated that Gulshan lake sediment was polluted with the chemical and bacterial pollutants. DOI: http://dx.doi.org/10.3329/jasbs.v38i2.15596 J. Asiat. Soc. Bangladesh, Sci. 38(2): 155-161, December 2012

Antimicrobial Activity of Iron-Halide Complexes Against Gram-Positive and Gram-Negative Bacteria

2020 ◽  
Author(s):  
Nusrat Abedin ◽  
Abdullah Hamed A Alshehri ◽  
Ali M A Almughrbi ◽  
Olivia Moore ◽  
Sheikh Alyza ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Antimicrobial Resistance ◽  
Extracellular Dna ◽  
Antibiofilm Activity ◽  
Gram Negative Bacteria ◽  
Bacterial Strains ◽  
Gram Positive ◽  
Gram Negative ◽  
Antimicrobial Substances ◽  
Mammalian Cell Lines

Antimicrobial resistance (AMR) has become one of the more serious threats to the global health. The emergence of bacteria resistant to antimicrobial substances decreases the potencies of current antibiotics. Consequently, there is an urgent and growing need for the developing of new classes of antibiotics. Three prepared novel iron complexes have a broad-spectrum antimicrobial activity with minimum bactericidal concentration (MBC) values ranging from 3.5 to 10 mM and 3.5 to 40 mM against Gram-positive and Gram-negative bacteria with antimicrobial resistance phenotype, respectively. Time-kill studies and quantification of the extracellular DNA confirmed the bacteriolytic mode of action of the iron-halide compounds. Additionally, the novel complexes showed significant antibiofilm activity against the tested pathogenic bacterial strains at concentrations lower than the MBC. The cytotoxic effect of the complexes on different mammalian cell lines show sub-cytotoxic values at concentrations lower than the minimum bactericidal concentrations.

scholarly journals Bacterial Isolates and its Antibiotic Susceptibility Pattern in NICU

2014 ◽  
Vol 11 (1) ◽  
pp. 66-70 ◽  
Author(s):  
S Shrestha ◽  
NC Shrestha ◽  
S Dongol Singh ◽  
RPB Shrestha ◽  
S Kayestha ◽  
...  
Keyword(s):  
Intensive Care Unit ◽  
Intensive Care ◽  
Neonatal Intensive Care Unit ◽  
Neonatal Intensive Care ◽  
Bacterial Isolates ◽  
Susceptibility Pattern ◽  
Gram Positive ◽  
Antibiotic Susceptibility Pattern ◽  
Gram Negative ◽  
Nosocomial Sepsis

Background Neonatal sepsis is one of the major causes of morbidity and mortality among the newborns in the developing world. Objectives To determine the common bacterial isolates causing sepsis in neonatal intensive care unit and its antibiotic susceptibility pattern. Methods A one year discriptive prospective study was conducted in neonatal intensive care unit to analyse the results of blood culture and to look into the sensitivity of the commonly used antibiotics. Results The blood culture yield by conventional method was 44.13% with nosocomial sepsis accounting for 10.79%. 84.08% were culture proven early onset sepsis and 15.95% were late onset sepsis. Klebsiella infection was the commonest organism isolated in early, late and nosocomial sepsis but statistically not significant. Gram positive organisms were 39.36% in which Staphylococcus aureus was the leading microorganism followed by coagulase negative staphylococcus areus. Gram negative organisms were 60.64% amongst them Klebsiella was the most often encountered followed by Pseudomonas. The most common organism Klebsiella was 87.5% and 78.3% resistance to ampicillin and gentamycin respectively. Among gram negative isolates 87.5% and 77.2% were resistance to ampicillin and gentamycin respectively. Among gram positive isolates 58.5% and 31.5% resistance were noted to ampicillin and gentamycin respectively. Resistance to cefotaxim to gram negative and gram positive isolates were 87.34% and 59.35% respectively. Conclusion Klebsiella is most common organism which is almost resistance to first line antibiotics. Resistance to both gram negative and gram positive isolates among firstline antibiotics and even with cefotaxim is emerging and is a major concern in neonatal intensive care unit. DOI: http://dx.doi.org/10.3126/kumj.v11i1.11030 Kathmandu University Medical Journal Vol.11(1) 2013: 66-70

scholarly journals Ultrasonic Irradiation: Synthesis, Characterization, and Preliminary Antimicrobial Activity of Novel Series of 4,6-Disubstituted-1,3,5-triazine Containing Hydrazone Derivatives

2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Hessa H. Al-Rasheed ◽  
Monirah Al Alshaikh ◽  
Jamal M. Khaled ◽  
Naiyf S. Alharbi ◽  
Ayman El-Faham
Keyword(s):  
Antimicrobial Activity ◽  
Ultrasonic Irradiation ◽  
New Products ◽  
Conventional Heating ◽  
Pyridine Derivative ◽  
Gram Negative Bacteria ◽  
Bacterial Strains ◽  
Gram Positive ◽  
Gram Negative ◽  
Antimicrobial And Antifungal Activities

Novel series of 4,6-disubstituted-1,3,5-triazines containing hydrazone derivatives were synthesized employing ultrasonic irradiation and conventional heating. The ultrasonication gave the target products in higher yields and purity in shorter reaction time compared with the conventional method. IR, NMR (H 1 and C 13), elemental analysis, and LC-MS confirmed the structures of the new products. The antimicrobial and antifungal activities were evaluated for all the prepared compounds against some selected Gram-positive and Gram-negative bacterial strains. The results showed that only two compounds 7i (pyridine derivative) and 7k (4-chlorobenzaldehyde derivative) displayed biological activity against some Gram-positive and Gram-negative bacteria, while the rest of the tested compounds did not display any antifungal activity.

scholarly journals Microwave Assisted Synthesis and Antimicrobial Evaluation of Schiff Bases of Indole-3-aldehyde

2011 ◽  
Vol 8 (1) ◽  
pp. 305-311 ◽  
Author(s):  
Priyanka Kamaria ◽  
N. Kawathekar ◽  
Prerna Chaturvedi
Keyword(s):  
Schiff Bases ◽  
Antimicrobial Agents ◽  
Microwave Assisted Synthesis ◽  
Bacterial Strains ◽  
Mass Spectral Analysis ◽  
Gram Positive ◽  
Gram Negative ◽  
Mass Spectral ◽  
Microwave Assisted ◽  
Antimicrobial Evaluation

In order to develop new antimicrobial agents, a series of Schiff bases of indole-3-aldehyde were synthesized by microwave assisted synthesis by takingDMFas solvent and evaluated for their antimicrobial activity. All the synthesized compounds were characterized byIR,1HNMRand mass spectral analysis. All compounds were tested against five gram positive and five gram negative bacterial strains and one fungal strain. All compounds exhibited better activity against gram positive strains than against gram negative strains and the compounds were found more active againstS.aureusandB.subtilis.

scholarly journals Anticancer and Antimicrobial Activity Evaluation of Cowpea-Porous-Starch-Formulated Silver Nanoparticles

2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Shiara Ramdath ◽  
John Mellem ◽  
Londiwe Simphiwe Mbatha
Keyword(s):  
Antimicrobial Activity ◽  
Silver Nanoparticles ◽  
Cell Viability ◽  
High Dose ◽  
Bacterial Strains ◽  
Gram Positive ◽  
Gram Negative ◽  
Anticancer Drug Delivery ◽  
Ic50 Values ◽  
Biosynthesized Agnps

Health issues involving inadequate treatment of diseases such as cancer and microbial infections continue to be the subject of much ongoing recent research. Biosynthesized silver nanoparticles (AgNPs) were characterized using Transmission Electron Microscopy (TEM), Zeta Sizer, Ultraviolet (UV), and Fourier Transform Infrared (FTIR) spectroscopy. Their antimicrobial activity was evaluated on selected Gram-positive and Gram-negative bacterial strains, using the disc diffusion and broth dilution assays. Cell viability profiles were evaluated using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) and apoptosis studies on selected human noncancer and cancer cells. The biosynthesized AgNPs were evaluated to be spherical clusters, with sizes between 40 and 70 nm. The absorption peak at 423 nm and the presence of polyphenols confirmed the synthesis and stabilization of these tested AgNPs. The AgNPs showed a good stability of −23.9 ± 1.02 mV. Good antimicrobial activity (6.0–18.0 mm) was seen on all tested bacteria at a minimum inhibitory concentration (MIC) ranging from 5 to 16 μg/ml, with the highest activity seen against Gram-negative Escherichia coli (18 ± 0.5 mm), and the lowest activity was seen against Gram-positive Listeria monocytogenes (6.0 ± 0.4 mm) after treatment with the AgNPs. These NPs showed a concentration-dependent and cell-specific cytotoxicity with low IC50 values (41.7, 56.3, and 63.8 μg/ml). The NPs were well tolerated by tested cells as indicated by a more than 50% cell viability at the high dose tested and low apoptotic indices (<0.2). These findings indicated that these biosynthesized AgNPs showed great potential as effective antibacterial agents and anticancer drug delivery modalities.

scholarly journals Microbiological Screening and Antimicrobial Sensitivity Profiling of Wound Infections in a Tertiary Care Hospital of Bangladesh

2020 ◽  
pp. 101-106
Keyword(s):  
Wound Infection ◽  
Primary Care Physicians ◽  
Tertiary Care Hospital ◽  
Tertiary Care ◽  
Treatment Modalities ◽  
Care Hospital ◽  
Bacterial Isolates ◽  
Gram Positive ◽  
Gram Negative ◽  
Antimicrobial Sensitivity

Wound infection is a major problem in hospitals in developing countries. Wound infection causes morbidity and prolonged hospital stay thus this prospective study was conducted for a period of seven months (January 2019 to July 2019). A total of 217 specimens (wound swabs and pus exudates) from wound infected patients in a Tertiary Care Hospital in Bangladesh. A retrospective study of the microbiological evaluation was done by cultural growth as well as Gram staining and biochemical examination to identify the bacterial isolates. Finally, the antimicrobial vulnerability testing was performed by Kirby-Bauer disc diffusion conventional method. A total of 295 samples were tested. Out of which 217 (73.5%) were found culture positive. E. coli was the most predominant gram-negative isolates whereas Staphylococcus aureus and Coagulase-negative Staphylococcus were the most commonly isolated gram-positive organisms. Antimicrobial sensitivity profile of bacterial isolates revealed imipenem, meropenem, amikacin, and nitrofurantoin to be the most effective antimicrobials against gram-negative isolates, whereas imipenem, meropenem, amikacin, nitrofurantoin, amoxiclav, and gentamicin were the most effective drugs against gram-positive isolates. The result of this examination contributes to the identification of basic causative microbes involved in wound infection and findings of antibiotic susceptibility patterns can be helpful for primary care physicians to optimize the treatment modalities, articulate policies for empiric antimicrobial therapy, and to minimize the rate of infection among wound infected patients.

scholarly journals Diversity and Antibiotic Susceptibility of Bacteria in Water of Hotel Restaurants in Dhaka City

2017 ◽  
Vol 43 (2) ◽  
pp. 173-180
Author(s):  
Md Abdul Karim ◽  
Nasrin Sultana
Keyword(s):  
Bacterial Abundance ◽  
Bacterial Count ◽  
Dhaka City ◽  
Bacterial Isolates ◽  
Genus Bacillus ◽  
Gram Positive ◽  
Gram Negative ◽  
Agar Media ◽  
Micrococcus Roseus ◽  
Microbiological Status

Present study was conducted to determine the microbiological status of water from dispensers in different roadside hotel and restaurants of Dhaka city. Samples were collected from seven hotel and restaurants. Aerobic heterotrophic bacterial count ranged between 1.5 × 10 and 8.8 × 103 cfu/ml. Enteric and related bacterial abundance in MacConkey, SS and Cetrimide agar media ranged from 0 to 4.9 × 106, 0 to 2.1 × 105 and 0 to 1.2 × 106cfu/ml, respectively. In total, 28 bacterial isolates were obtained during the study period. Among them, 15 were heterotrophic isolates and 13 were enteric and related bacteria. Among 15 aerobic heterotrophic isolates, 11 were gram positive and five were gram negative. Out of 11 gram positive isolates, 7 belonged to the genus Bacillus viz. B. circulans, B. subtilis, B. stearothermophilus, B. brevis and B. cereus and one to coccus viz. Micrococcus roseus. The other gram positive species were Kurtia gibsonii, Auriobacterium liguefaciens and Curtobacterium luteum. Four gram negative isolates were Neisseria elongate sub. spp. glycolytica, Plesiomonas shigelloides, Pseudomonas fluorescens biovar 1, Pseudomonas aeruginosa. All 13 enteric and related isolates were gram negative, short rod; and non-spore formers and belonged to the genera Escherichia, Klebsiella, Shigella and Pseudomonas. Among all isolates, two were resistant and six were susceptible to all five antibiotics. Asiat. Soc. Bangladesh, Sci. 43(2): 173-180, December 2017

Sign in / Sign up

Export Citation Format

Share Document