The production methods of selenium nanoparticles

Abstract In recent years, the application of selenium nanoparticles has been increasing in medicine, agriculture, engineering, and food science. Therefore, researchers are converting inorganic selenium sources into nano form by various methods. Particularly both probiotics and pathogenic bacterial strains have the ability to synthesize selenium nanoparticles under aerobic and anaerobic conditions. Amazingly, dose-dependent selenium nanoparticles have antibacterial activity against their own pathogenic producer, even when added externally. Also, plant extracts and conventional chemical reducing agents continue to make a significant contribution to the production of selenium nanoparticles in an economic, eco-friendly, simple, and rapid way. Biological and chemical methods are suitable for the biological applications of selenium nanoparticles such as functional food or nutritional supplements and nanomedicine.

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Calcite and vaterite biosynthesis by nitrate dissimilating bacteria in carbonatogenesis process under aerobic and anaerobic conditions

10.5194/bg-2019-444 ◽

2019 ◽

Author(s):

Marwa Eltarahony ◽

Sahar Zaki ◽

Ayman Kamal ◽

Desouky Abd-El-Haleem

Keyword(s):

Nitrate Reduction ◽

Reductase Activity ◽

Specific Property ◽

Bacterial Strains ◽

Anaerobic Conditions ◽

Lysinibacillus Sphaericus ◽

Nucleation Sites ◽

First Time ◽

Aerobic And Anaerobic ◽

Aerobic And Anaerobic Conditions

Abstract. This study deals with 16S rDNA identified bacteria, Lysinibacillus sphaericus (71A), Raoultella planticola (VIP), and Streptomyces pluricolorescens (EM4) capable of precipitating CaCO3 through a nitrate reduction aerobically and anaerobically. The produced CaCO3 crystals were analyzed using XRD, EDX, and SEM. The results showed that the carbonatogenic bacteria served as nucleation sites for CaCO3 precipitation with distinct variation in polymorph and morphology; reflecting strain-specific property. Notably, the amount of precipitated CaCO3 recorded 3.27 (aerobic), 1.55 (anaerobic), 4.15 (aerobic), 3.75 (aerobic) and 1.87 (anaerobic) g/100 mL of strains 71A, EM4 and VIP, respectively, for 240 h of incubation. The study of changes in media chemistry during carbonatogenesis process revealed positive correlation between bacterial growth, nitrate reductase activity, pH, EC, amount of deposited CaCO3 and NO3− consumption. Therefore, the applications of these bacterial strains, which employed for the first time in carbonatogenesis process, are promising in the environmental, biomedical and civil engineering fields.

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Influence of aerobic and anaerobic conditions on the growth and metabolism of selected strains of Lactobacillus plantarum

Acta Chimica Slovaca ◽

10.2478/v10188-012-0031-1 ◽

2012 ◽

Vol 5 (2) ◽

pp. 204-210 ◽

Cited By ~ 10

Author(s):

Jana Smetanková ◽

Zuzana Hladíková ◽

František Valach ◽

Michaela Zimanová ◽

Zlatica Kohajdová ◽

...

Keyword(s):

Acetic Acid ◽

Lactic Acid ◽

Lactobacillus Plantarum ◽

Ph Value ◽

Cell Yield ◽

Bacterial Strains ◽

Anaerobic Conditions ◽

Wild Strains ◽

Aerobic And Anaerobic ◽

Aerobic And Anaerobic Conditions

Abstract Three wild strains of Lactobacillus plantarum were investigated for their growth and ability to produce lactic acid, acetic acid and ethanol under aerobic and anaerobic conditions. They were tested at three different temperatures (30 °C, 37 °C and 45 °C). The growth of lactobacilli was studied by measuring optical density (OD) at λ = 600 nm and pH value at the following times. With increasing temperature difference of cell yield was observed. The final cell yield under aerobic conditions was higher. Organic acids and ethanol were analysed using an HPLC RID method. Formation of lactic acid (as the major metabolite) was the slowest during cultivation at 30 °C, but the final amount of lactic acid showed the highest values. Concentrations of metabolites produced by lactobacilli after 48th hours of cultivation were: 9.18-11.48 g.dm-3 (lactic acid), 0.84-1.65 g.dm-3 (acetic acid) and 2.51-4.03 g.dm-3 (ethanol). No significant differences (p = 0.05) were found in production of lactic acid and ethanol by different bacterial strains under aerobic and anaerobic conditions. Statistically significant differences (p = 0.05) were observed in production of acetic acid by 2L2 under aerobic and anaerobic conditions and for production of ethanol under anaerobic conditions by strains 1L5 and 2L2.

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Microbial Communities Associated with Acetaminophen Biodegradation from Mangrove Sediment

Sustainability ◽

10.3390/su12135410 ◽

2020 ◽

Vol 12 (13) ◽

pp. 5410

Author(s):

Chu-Wen Yang ◽

Yi-En Chen ◽

Bea-Ven Chang

Keyword(s):

Microbial Communities ◽

Electron Acceptors ◽

Mangrove Sediment ◽

Bacterial Strains ◽

Anaerobic Conditions ◽

Mushroom Compost ◽

Mangrove Sediments ◽

Spent Mushroom Compost ◽

Aerobic And Anaerobic ◽

Aerobic And Anaerobic Conditions

Acetaminophen (ACE) is a widely used medicine. Currently, concerns regarding its potential adverse effects on the environments are raised. The aim of this study was to evaluate ACE biodegradation in mangrove sediments under aerobic and anaerobic conditions. Three ACE biodegradation strategies in mangrove sediments were tested. The degradation half-lives (t1/2) of ACE in the sediments with spent mushroom compost under aerobic conditions ranged from 3.24 ± 0.16 to 6.25 ± 0.31 d. The degradation half-lives (t1/2) of ACE in sediments with isolated bacterial strains ranged from 2.54 ± 0.13 to 3.30 ± 0.17 d and from 2.62 ± 0.13 to 3.52 ± 0.17 d under aerobic and anaerobic conditions, respectively. The degradation half-lives (t1/2) of ACE in sediments amended with NaNO3, Na2SO4 and NaHCO3 under anaerobic conditions ranged from 1.16 ± 0.06 to 3.05 ± 0.15 d, 2.39 ± 0.12 to 3.84 ± 0.19 d and 2.79 ± 0.14 to 10.75 ± 0.53 d, respectively. The addition of the three electron acceptors enhanced ACE degradation in mangrove sediments, where NaNO3 yielded the best effects. Sixteen microbial genera were identified as the major members of microbial communities associated in anaerobic ACE degradation in mangrove sediments with addition of NaNO3 and Na2SO4. Three (Arthrobacter, Enterobacter and Bacillus) of the sixteen microbial genera were identified in the isolated ACE-degrading bacterial strains.

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Biodegradation of Amoxicillin, Tetracyclines and Sulfonamides in Wastewater Sludge

Water ◽

10.3390/w12082147 ◽

2020 ◽

Vol 12 (8) ◽

pp. 2147 ◽

Cited By ~ 3

Author(s):

Chu-Wen Yang ◽

Chien Liu ◽

Bea-Ven Chang

Keyword(s):

Microbial Communities ◽

Anaerobic Degradation ◽

Wastewater Sludge ◽

Bacillus Sp ◽

Batch Experiments ◽

Bacterial Strains ◽

Anaerobic Conditions ◽

Degrading Bacteria ◽

Aerobic And Anaerobic ◽

Aerobic And Anaerobic Conditions

The removal of antibiotics from the aquatic environment has received great interest. The aim of this study is to examine degradation of oxytetracycline (OTC), tetracycline (TC), chlortetracycline (CTC), amoxicillin (AMO), sulfamethazine (SMZ), sulfamethoxazole (SMX), sulfadimethoxine (SDM) in sludge. Four antibiotic-degrading bacterial strains, SF1 (Pseudmonas sp.), A12 (Pseudmonas sp.), strains B (Bacillus sp.), and SANA (Clostridium sp.), were isolated, identified and tested under aerobic and anaerobic conditions in this study. Batch experiments indicated that the addition of SF1 and A12 under aerobic conditions and the addition of B and SANA under anaerobic conditions increased the biodegradation of antibiotics in sludge. Moreover, the results of repeated addition experiments indicated that the efficiency of the biodegradation of antibiotics using the isolated bacterial strains could be maintained for three degradation cycles. Two groups of potential microbial communities associated with the aerobic and anaerobic degradation of SMX, AMO and CTC in sludge were revealed. Twenty-four reported antibiotics-degrading bacterial genera (Achromobacter, Acidovorax, Acinetobacter, Alcaligenes, Bacillus, Burkholderia, Castellaniella, Comamonas, Corynebacterium, Cupriavidus, Dechloromonas, Geobacter, Gordonia, Klebsiella, Mycobacterium, Novosphingobium, Pandoraea, Pseudomonas, Rhodococcus, Sphingomonas, Thauera, Treponema, Vibrio and Xanthobacter) were found in both the aerobic and anaerobic groups, suggesting that these 24 bacterial genera may be the major antibiotic-degrading bacteria in sludge.

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Cultivable Oral Microbiota in Puppies

Folia Veterinaria ◽

10.2478/fv-2021-0029 ◽

2021 ◽

Vol 65 (3) ◽

pp. 69-74

Author(s):

J. Kačírová ◽

Ľ. Horňáková ◽

A. Maďari ◽

K. Mravcová ◽

M. Maďar

Keyword(s):

Caesarean Section ◽

16S Rrna ◽

Sanger Sequencing ◽

Caesarean Delivery ◽

The Other ◽

Oral Microbiota ◽

Bacterial Strains ◽

Anaerobic Conditions ◽

Aerobic And Anaerobic ◽

Aerobic And Anaerobic Conditions

Abstract The oral microbiota has been shown to be different in children born by caesarean section and delivered vaginally. The aim of this study was to investigate the oral microbial diversity in healthy puppies and to determine whether the birth mode affects the composition of the oral microbiota. A total of 19 puppies from 4 dams were included in the study. The puppies were divided into two groups depending on the birth mode, vaginal delivery (vaginal born VB) or caesarean delivery (caesar-ean section CS). On the seventh day after birth, swabs of the oral cavity were taken. All samples were analysed by bacteriological cultivation under aerobic and anaerobic conditions. Bacterial colonies were identified by Sanger sequencing of 16S rRNA. A total of 64 bacterial strains belonging to 10 genera were obtained from the oral swabs. The genera Staphylococcus (30.23 % VB and 47.62 % CS) and Enterococcus (25.58 % VB and 33.33 % CS) were the most abundant in both groups. The genera Escherichia (18.60 %) and Enterobacter (16.28 %) were largely present in puppies delivered vaginally, they were not found in puppies born by caesarean section. The other detected genera were present at lower proportions (< 5 %) and varied between the groups. The oral micro-biota of the puppies in the litter was similar, but differed between litters and between groups. Based on these results, we can assume that the birth mode affects the oral microbiota of puppies.

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