scholarly journals Bacterial Cellulose (BC) and BC Composites: Production and Properties

Nanomaterials ◽  
2022 ◽  
Vol 12 (2) ◽  
pp. 192
Author(s):  
Tatiana G. Volova ◽  
Svetlana V. Prudnikova ◽  
Evgeniy G. Kiselev ◽  
Ivan V. Nemtsev ◽  
Alexander D. Vasiliev ◽  
...  

The synthesis of bacterial cellulose (BC) by Komagataeibacter xylinus strain B-12068 was investigated on various C-substrates, under submerged conditions with stirring and in static surface cultures. We implemented the synthesis of BC on glycerol, glucose, beet molasses, sprat oil, and a mixture of glucose with sunflower oil. The most productive process was obtained during the production of inoculum in submerged culture and subsequent growth of large BC films (up to 0.2 m2 and more) in a static surface culture. The highest productivity of the BC synthesis process was obtained with the growth of bacteria on molasses and glycerol, 1.20 and 1.45 g/L per day, respectively. We obtained BC composites with silver nanoparticles (BC/AgNPs) and antibacterial drugs (chlorhexidine, baneocin, cefotaxime, and doripenem), and investigated the structure, physicochemical, and mechanical properties of composites. The disc-diffusion method showed pronounced antibacterial activity of BC composites against E. coli ATCC 25922 and S. aureus ATCC 25923.

2021 ◽  
Vol 7 (2) ◽  
pp. 47-51
Author(s):  
Prayoga Pannindrya ◽  
Mega Safithri ◽  
Kustiariyah Tarman

Spirulina is a microalgae that has been widely used as various supplements and medicines because of its high nutritional content. The need for new antibacterial sources to solve the problem of antibiotic resistance, makes the potential of Spirulina as an antibacterial agent necessary to be researched. This study aims to analyze the antibacterial activity of ethanol extract of Spirulina platensis obtained from the Indonesian region against Staphylococcus aureus and Escherichia coli. Spirulina samples were macerated in ethanol solvent in a ratio of 1:10 (w / v). The antibacterial test used was the disc diffusion method with clindamycin positive control. Antibacterial test results showed that S. platensis in this study did not have antibacterial activity against E. coli and S. aureus.


2019 ◽  
Vol 31 (5) ◽  
pp. 1077-1080
Author(s):  
Kottakki Naveen Kumar ◽  
Karteek Rao Amperayani ◽  
V. Ravi Sankar Ummdi ◽  
Uma Devi Parimi

A series 1,2,4-triazole piperine analogues (TP1-TP6) were designed and synthesized. The structures were confirmed using 1H NMR and 13C NMR. Antibacterial study was done using Gram-positive (Staphylococcus aureus and Bacillus cereus) and Gram-negative micro-organisms (E. coli and Pseudomonas aeruginosa) by disc diffusion method. Compound containing chloro substitution (TP6) showed the highest effect, while compound TP1, TP3, TP4, TP5 showed the moderate activity.


2018 ◽  
Vol 34 (5) ◽  
pp. 2495-2501 ◽  
Author(s):  
Sarmd D. Noori ◽  
Mazin N. Mousa ◽  
Shaker A. N. Al-Jadaan

Five compounds containing (2,4,5-triphenyl triphenyl-1H-) and azetidinone (beta-lactam) moiety were synthesized. The physical data and yield of synthesized compounds were recorded, the chemical structure of prepared compounds were characterized using FT-IR, 1H-NMR and elemental analysis. The antibacterial activity was evaluated using disc diffusion method that involve tow Gram positive (staph. aureus, E. Faecalis), two Gram negative (E. coli and ‎K. pneumoniae), and one anaerobic bacteria (streptococcus. Pyogen). Different concentration of the prepared compounds has been used, and the obtained result were compared with standard (ceftazidime). Compound (5c) showed the best antibacterial activity against all bacterial species while 5a and 5e does not. Other compounds showed activity against some species.


2011 ◽  
Vol 2011 ◽  
pp. 1-7 ◽  
Author(s):  
Comfort Nkogwe ◽  
Juliah Raletobana ◽  
Alva Stewart-Johnson ◽  
Sharianne Suepaul ◽  
Abiodun Adesiyun

The study was conducted to determine the frequency of isolation ofSalmonella,CampylobacterandE. coliO157 in the faecal samples of rats trapped across the regional corporations in Trinidad and to assess their resistance to antimicrobial agents. A total of 204 rats were trapped for the detection of selected bacteria. Standard methods were used to isolateSalmonella,CampylobacterandE. coliO157. Characterization ofE. coliwas done on sorbitol MacConkey agar to determine non-sorbitol fermentation, blood agar to determine haemolytic and mucoid colonies and by usingE. coliO157 antiserum to determine O157 strain. The disc diffusion method was used to determine resistance to nine antimicrobial agents. Of the 204 rats, 4 (2.0%), 7 (3.4%) and 171 (83.8%) were positive forSalmonellaspp.,Campylobacterspp. andE. coli, respectively. Of the 171 isolates ofE. colitested 0 (0.0%), 25 (14.6%) and 19 (11.1%) were haemolytic, mucoid and non-sorbitol fermenters, respectively. All isolates were negative for the O157 strain. The frequency of resistance to the 9 antimicrobial agents tested was 75% (3 of 4) forSalmonella, 85.7% (6 of 7) ofCampylobacterspp. and 36.3% (62 of 171) forE. coli(;χ2).


Author(s):  
Halima Benachour ◽  
Messaoud Ramdani ◽  
Takia Lograda ◽  
Pierre Chalard ◽  
Gilles Figueredo

Abstract. Benachour H, Ramdani M, Lograda T, Chalard P, Figueredo J. 2020. Chemical composition and antibacterial activities of Capparis spinosa essential oils from Algeria. Biodiversitas 21: 161-169. The essential oils of Capparis spinosa L. collected from six locations in Algeria were obtained by hydro-distillation. The chemical composition of oils was performed by GC-MS. The disc diffusion method is applied for the antibacterial activity. The extraction produced low yield (0.03%). The result of chromatographic analysis (GC/MS) leads to the identification of 33 components; palmitic acid (38.19%), nonanal-n (12.61%), cymene-2,5-dimethoxy-para (8.94%) and octacosane (5.49%) were the major components of these oils. The result of cluster analysis based on essential oils constituents showed the presence of three chemotypes,i.e., the chemotype of Nonanal-n-Cymen 2,5 dimethoxy para-Dodecanal, the chemotype of Nonanal-n-Hexadecanoic acid-tetracosane and the chemotype Tetracosane-n-pentyl furane-2-octacosane. In-vitro antimicrobial activity of caper oils against nine bacterial species showed that the oils have no activity against E. coli and have modest activities against eight other bacterial species tested; however, the desirability test shows that the oils used were not effective on the bacteria tested.


2021 ◽  
Vol 30 (1) ◽  
pp. 101-106
Author(s):  
K. F. Chah ◽  
S. C. Okafor ◽  
S. I. Oboegbulem

This study was carried out to determine resistance profiles of Escherichia coli strains isolated from clinically healthy chickens in Nsukka, southeast Nigeria. A total of 324 E. coli strains isolated from cloaca swabs from 390 chickens were tested against 16 antimicrobial agents using the disc diffusion method. The antibiotics used in the study were: ampicillin (25µg), amoxycillin-clavulanic acid (30µg), gentamicin (10µg), Streptomycin (30µg). cefuroxime (20µg), cephalexin (10µg), nalidixic acid (30µg), ciprofloxacin (5µg), norfloxacin (10µg), ofloxacin (5µg), pefloxacin (5µg), tetracycline (30µg), chloramphenicol (10µg), cotrimoxazole (50µg), colistin (25µg) and nitrofurantoin (100µg).The strains demonstrated high rates of resistance (34.6%  66.1%) to ampicillin, tetracycline, nitrofurantoin, cefuroxime and cotrimoxazole. None of the isolates was resistant to colistin, ofloxacin and pefloxacin. For each antimicrobial agent (except cephalexin), strains from the intensively reared chickens (layers and broilers) displayed higher resistance frequencies than those from the local birds. A total of 49 resistant patterns were recorded for the 228 strains resistant to at least one antimicrobial drug, with AmTeCoS and AmTeCfN being the predominant patterns. Because of the great variation in the drug resistance patterns of the Escherichia coli strains, use of antimicrobial agents in the management of E. coli infections in the study area should be based on results of sensitivity tests.


2016 ◽  
Vol 30 (1-2) ◽  
pp. 23-29
Author(s):  
Sheikh Shahidul Islam ◽  
Md Abdul Malek ◽  
AKM Fazlul Haque ◽  
Kaisar Ali Talukder ◽  
Marufa Zerin Akhter

A microbiological study was carried out to determine the prevalence of extended spectrum beta lactamase (ESBL) producing E. coli in anorectal sepsis patients in Bangladesh. One hundred specimens of pus, swab, or exudates from anorectal sepsis cases were studied. All the 61 isolates of E. coli were found to be highly resistant to most of the drugs used. Among these, 14 multidrug resistant E. coli were examined for ESBL production by double disc diffusion method. Six of these were found to be ESBL positive. PCR analysis revealed that 3 of the 6 isolates had coexistence of blaSHV, blaOXA and blaCTXM-1 genes. Two of the isolates had only blaSHV gene, whereas 1 isolate had a combination of blaTEM and blaSHV genes. Three of these were resistant to all the drugs tested, while two were sensitive to getamicin and one to ciprofloxacin. None of the E. coli strains possessed blaCTXM-2, blaCTXM-8, blaCTXM-9, and qnr genes.Bangladesh J Microbiol, Volume 30, Number 1-2,June-Dec 2013, pp 23-29


2003 ◽  
Vol 9 (2) ◽  
pp. 85-88 ◽  
Author(s):  
G. Özkan ◽  
O. Sağdiç ◽  
M. Özcan

The antimicrobial effect of 11 selected Turkish spice essential oils was investigated against seventeen pathogenic bacteria. The antimicrobial activity of the essential oils of six spices (cumin, fennel, laurel, mint, marjoram, oregano, pickling herb, sage, savory, thyme (black) and thyme) was tested at four concentrations (0.2, 0.4, 1 and 2%) on various microorganisms ( E. aerogenes, E. coli, E. coli O157:H7, K. pneumoniae, P. vulgaris, S. enteritidis, S. gallinarum, S. typhimurium, S. aureus, Y. enterocolitica, A. hydrophila, C. xerosis, M. luteus, M. smegmatis, E. feacalis, P. aeruginosa and P. fluorescens). All preparations showed antibacterial activity against at least one or more bacteria. The inhibitory effect of the essential oils was evaluated through paper disc diffusion method. In general, the essential oils at 1 and 2% levels were effective. The most active essential oils were marjoram, thyme and oregano. According to the results, the studied essential oils potentially might be used as antibacterial agents to prevent the spoilage of food products, although further research is needed.


2020 ◽  
pp. 1-2
Author(s):  
Spriha Smriti ◽  
Babita Kumari ◽  
Pratulya Nandan

Introduction- Osteomyelitis refers to infection of bone marrow which spread to the bone cortex and periosteum. Osteomyelitis is most commonly caused by pyogenic bacteria. Despite greater advances in treatment the management of osteomyelitis is quite challenging due to increasing development of antibiotic resistance. Material and Methods -100 patients were evaluated. Samples like pus or exudates or pieces of necrotic tissue were taken. Samples were subjected to gram’s staining and culture. Antimicrobial sensitivity was done using Kirby Bauer disc diffusion method. RESULTS - Staphylococcus aureus was the most common organism isolated followed by E.coli, Klebsiella pneumoniae P. aeuroginosa and Proteus. Staphylococcus aureus + E coli was the most common polymicrobial organism isolated. In trauma cases most common organism isolated was Staphylococcus aureus. Gentamycin was the commonest antibiotic which was effective for treatment of osteomyelitis followed by amikacin, tobramycin and levofloxacin.In cases of gram positive organism max were seen to sensitive to vancomycin and linezolid.


2018 ◽  
Vol 39 (4) ◽  
pp. 457-462
Author(s):  
Phan Thi Hoai Trinh ◽  
Ngo Thi Duy Ngoc ◽  
Vo Thi Dieu Trang ◽  
Le Quoc Phong ◽  
Phi Quyet Tien ◽  
...  

Marine fungi have become an important source of bioactive natural products. The present study was concerned with the screening of antimicrobial activity from 73 fungal strains isolated from various marine habitats collected from five different localities at the Son Tra Peninsula, Da Nang, Vietnam. For the first step of screening, ethyl acetate extract of each fungal isolate was prepared and their antimicrobial activity against the human microbial pathogens was investigated using the disc diffusion method. The panel of human microbial pathogens used were Bacillus cereus ATCC 11778, Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 25923, Pseudomonas aeruginosa ATCC 27853, Listeria monocytogenes ATCC 19111, Streptococcus faecalis ATCC 19433 and Candida albicans ATCC 10231. Among 73 fungal isolates, 29 exhibited antimicrobial activity against at least two tested pathogens. The proportion of the fungal isolates having anti-microbial activity against B. cereus, S. faecalis, L. monocytogenes, S. aureus, E. coli, C. albicans and P. aeruginosa were 42, 33, 31, 22, 7, 5 and 3%, respectively. Further investigations to isolate and characterize the anti-microbial components in the extracts are needed.   Citation: Phan Thi Hoai Trinh, Ngo Thi Duy Ngoc, Vo Thi Dieu Trang, Le Quoc Phong, Phi Quyet Tien, Bui Minh Ly, Tran Thi Thanh Van, 2017. Antimicrobial activity of marine fungi isolated from the Son Tra peninsula, Da Nang, Vietnam. Tap chi Sinh hoc, 39(4): 457-462. DOI: 10.15625/0866-7160/v39n4.8889. *Corresponding author: [email protected] Received 20 November 2016, accepted 12 August 2017 


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