scholarly journals Phenol Removal Capacity of the Common Duckweed (Lemna minor L.) and Six Phenol-Resistant Bacterial Strains From Its Rhizosphere: In Vitro Evaluation at High Phenol Concentrations

Plants ◽  
2020 ◽  
Vol 9 (5) ◽  
pp. 599
Author(s):  
Olga Radulović ◽  
Slaviša Stanković ◽  
Branka Uzelac ◽  
Vojin Tadić ◽  
Milana Trifunović-Momčilov ◽  
...  

The main topic of this study is the bioremediation potential of the common duckweed, Lemna minor L., and selected rhizospheric bacterial strains in removing phenol from aqueous environments at extremely high initial phenol concentrations. To that end, fluorescence microscopy, MIC tests, biofilm formation, the phenol removal test (4-AAP method), the Salkowski essay, and studies of multiplication rates of sterile and inoculated duckweed in MS medium with phenol (200, 500, 750, and 1000 mg L−1) were conducted. Out of seven bacterial strains, six were identified as epiphytes or endophytes that efficiently removed phenol. The phenol removal experiment showed that the bacteria/duckweed system was more efficient during the first 24 h compared to the sterile duckweed control group. At the end of this experiment, almost 90% of the initial phenol concentration was removed by both groups, respectively. The bacteria stimulated the duckweed multiplication even at a high bacterial population density (>105 CFU mL−1) over a prolonged period of time (14 days). All bacterial strains were sensitive to all the applied antibiotics and formed biofilms in vitro. The dual bacteria/duckweed system, especially the one containing strain 43-Hafnia paralvei C32-106/3, Accession No. MF526939, had a number of characteristics that are advantageous in bioremediation, such as high phenol removal efficiency, biofilm formation, safety (antibiotic sensitivity), and stimulation of duckweed multiplication.

2021 ◽  
Author(s):  
Dibakar Roy ◽  
Dasari Sreekanth ◽  
Deepak Pawar ◽  
Himanshu Mahawar ◽  
Kamal K. Barman

Arsenic (As) is the one the most toxic element present in earth which poses a serious threat to the environment and human health. Arsenic contamination of drinking water in South and Southeast Asia reported one of the most threatening problems that causes serious health hazard of millions of people of India and Bangladesh. Further, use of arsenic contaminated ground water for irrigation purpose causes entry of arsenic in food crops, especially in Rice and other vegetable crops. Currently various chemical technologies utilized for As removal from contaminated water like adsorption and co-precipitation using salts, activated charcoal, ion exchange, membrane filtration etc. are very costly and cannot be used for large scale for drinking and agriculture use. In contrast, phytoremediation utilizes green plats to remove pollutants from contaminated water using various mechanisms such as rhizofiltration, phytoextraction, phytostabilization, phytodegrartion and phytovolatilization. A large numbers of terrestrial and aquatic weed flora have been identified so far having hyper metal, metalloid and organic pollutant removal capacity. Among the terrestrial weed flora Arundo donax, Typha latifolia, Typha angustifolia, Vetivaria zizinoids etc. are the hyper As accumulator. Similarly Eicchornea crassipes (Water hyacinth), Pistia stratiotes (water lettuce), Lemna minor (duck weed), Hyrdilla verticillata, Ceratophyllum demersum, Spirodella polyrhiza, Azola, Wolfia spp., etc. are also capable to extract higher amount of arsenic from contaminated water. These weed flora having As tolerance mechanism in their system and thus remediate As contaminated water vis-à-vis continue their life cycle. In this chapter we will discuss about As extraction potential of various aquatic and semi aquatic weeds from contaminated water, their tolerance mechanism, future scope and their application in future world mitigating As contamination in water resources.


Author(s):  
KAMNI RAJPUT ◽  
RAMESH CHANDRA DUBEY

Objective: In vitro antioxidant activity, in vivo antidiabetic property and intestinal attachment by two potential probiotic bacterial strains, namely, Enterococcus faecium and Enterococcus hirae were studied using albino rats. Methods: Antioxidant the activity was assessed using 2,2-Diphenyl-1-picrylhydrazyl radicals scavenging assay. Alloxan was administered intraperitoneally to induce diabetic conditions in experimental rats. Animals were treated with oral administration of Enterococcus spp., such as E. faecium, and E. hirae isolated from goat and sheep milk. The control animal group received normal saline for the same days. Glibenclamide drug was used as a positive control against probiotic bacterial cells. Results: However, administration of probiotic bacterial strains E. faecium and E. hirae, in albino rats significantly (p<0.05) at varying doses lowered blood glucose levels in diabetic rats as compared to the diabetic control group. Both the species of Enterococcus increased the bodyweight of experimental rats. However, E. faecium was the best antidiabetic strain having the antioxidant activities also in comparison to E. hirae. The attachment of probiotic bacterial cells E. faecium on the rat’s intestine wall against pathogens was examined. Furthermore, E. faecium showed its aggregation with pathogens by attachment of the intestines of albino rats. This showed that both the bacterial strains exhibited in vivo antidiabetic effect. Conclusion: The results of this study showed that probiotic bacteria possess antioxidant, antidiabetic activities, and attachment of intestine.


PEDIATRICS ◽  
1951 ◽  
Vol 7 (2) ◽  
pp. 269-293
Author(s):  
CHARLES C. CHAPPLE

A study has been made of the known phenomena which affect the biologic organism. Certain correlations have been found and other correlations are logically inferred. The common grounds of anatomic structures, the anatomic responses to endocrine stimuli, the interrelationships and interdependencies of the endocrines and external stimuli have been followed and have been related to cellular permeability and hyaluronic acid. Cellular phases, including the rhythmic alternations in physiologic functions, have been delineated and their importance stressed. Further, the probability is advanced that this rhythmicity originates physiologically in the brain but that the brain itself is capable of receiving transmissions from within and without the body, and disseminating them, again rhythmically, in normal or altered amplitude and frequency. Further experimental evidence of these correlations and their practical extrapolations into drug actions and the therapy of infections and metabolic disease will be reported and will include clinical, animal and in vitro studies. At present, the following conclusions seem justified: 1. No component of the body is capable of independent action. 2. Action in any component is reflected, according to its magnitude and directness of application, upon all the body. 3. All such actions are mediated by the brain. 4. There is a dynamic, rhythmic cyclicity in physiologic action which can be altered in amplitude and frequency. 5. These rhythms are alternations of cellular tenseness and relaxation. 6. The concomitants of the tense phase are compactness, impermeability, electric conductivity and contraction of all cells, and these characteristics might be described collectively as the factors operative in maturing the cell. The concomitants of the relaxed phase are laxness, permeability, electric resistance and expansion of all cells and are factors of growth. 7. The phase of tenseness is accompanied by an increase in certain hormonal activities and that of relaxation by an increase in others. 8. The hormones may be causes of the phase or the results of it. 9. Infectious disease cannot act as an extraneous agent capable of bringing its own engine into such a highly integrated mechanism but must act on the body through its ability to affect one of the body's mechanisms. 10. Drugs must act through the same channels available to disease. 11. Foods may contain, in addition to their caloric content, components capable of stimulating either the phase of cellular expansion or cellular compaction, particularly foods from the reproductive systems of plants or animals (milk, eggs, cereal, for example). 12. Vitamins each stimulate one phase and should be evaluated in terms of positive actions. 13. Inherent growth and maturation factors are not of fixed capacity in an individual but beyond certain limits must be supplied him or applied to him constantly. 14. The hormone most manifest in the tense phase is estrogen and so may be considered the maturation factor, and the one most manifest in the phase of relaxation or cell division is progesterone, which may be considered the growth factor.


PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e2458 ◽  
Author(s):  
Bruna Raquel Zancopé ◽  
Vanessa B. Dainezi ◽  
Marinês Nobre-dos-Santos ◽  
Sillas Duarte ◽  
Vanessa Pardi ◽  
...  

BackgroundA carbon dioxide (CO2) laser has been used to morphologically and chemically modify the dental enamel surface as well as to make it more resistant to demineralization. Despite a variety of experiments demonstrating the inhibitory effect of a CO2laser in reduce enamel demineralization, little is known about the effect of surface irradiated on bacterial growth. Thus, this in vitro study was preformed to evaluate the biofilm formation on enamel previously irradiated with a CO2laser (λ = 10.6 µM).MethodsFor this in vitro study, 96 specimens of bovine enamel were employed, which were divided into two groups (n = 48): 1) Control-non-irradiated surface and 2) Irradiated enamel surface. Biofilms were grown on the enamel specimens by one, three and five days under intermittent cariogenic condition in the irradiated and non-irradiated surface. In each assessment time, the biofilm were evaluated by dry weigh, counting the number of viable colonies and, in fifth day, were evaluated by polysaccharides analysis, quantitative real time Polymerase Chain Reaction (PCR) as well as by contact angle. In addition, the morphology of biofilms was characterized by fluorescence microscopy and field emission scanning electron microscopy (FESEM). Initially, the assumptions of equal variances and normal distribution of errors were conferred and the results are analyzed statistically by t-test and Mann Whitney test.ResultsThe mean of log CFU/mL obtained for the one-day biofilm evaluation showed that there is statistical difference between the experimental groups. When biofilms were exposed to the CO2laser, CFU/mL and CFU/dry weight in three day was reduced significantly compared with control group. The difference in the genes expression (Glucosyltransferases (gtfB) and Glucan-binding protein (gbpB)) and polysaccharides was not statically significant. Contact angle was increased relative to control when the surface was irradiated with the CO2laser. Similar morphology was also visible with both treatments; however, the irradiated group revealed evidence of melting and fusion in the specimens.ConclusionIn conclusion, CO2laser irradiation modifies the energy surface and disrupts the initial biofilm formation.


Antibiotics ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 279
Author(s):  
Md. Shahed-Al-Mahmud ◽  
Rakesh Roy ◽  
Febri Gunawan Sugiokto ◽  
Md. Nazmul Islam ◽  
Ming-Der Lin ◽  
...  

Biofilm formation is one of the main causes of increased antibiotic resistance in Acinetobacter baumannii infections. Bacteriophages and their derivatives, such as tail proteins with depolymerase activity, have shown considerable potential as antibacterial or antivirulence agents against bacterial infections. Here, we gained insights into the activity of a capsular polysaccharide (CPS) depolymerase, derived from the tailspike protein (TSP) of φAB6 phage, to degrade A. baumannii biofilm in vitro. Recombinant TSP showed enzymatic activity and was able to significantly inhibit biofilm formation and degrade formed biofilms; as low as 0.78 ng, the inhibition zone can still be formed on the bacterial lawn. Additionally, TSP inhibited the colonization of A. baumannii on the surface of Foley catheter sections, indicating that it can be used to prevent the adhesion of A. baumannii to medical device surfaces. Transmission and scanning electron microscopy demonstrated membrane leakage of bacterial cells treated with TSP, resulting in cell death. The therapeutic effect of TSP in zebrafish was also evaluated and the results showed that the survival rate was significantly improved (80%) compared with that of the untreated control group (10%). Altogether, we show that TSP derived from φAB6 is expected to become a new antibiotic against multi-drug resistant A. baumannii and a biocontrol agent that prevents the formation of biofilms on medical devices.


2018 ◽  
Author(s):  
Shi-qi An ◽  
Julie Murtagh ◽  
Kate B. Twomey ◽  
Manoj K. Gupta ◽  
Timothy P. O’Sullivan ◽  
...  

ABSTRACTThe opportunistic pathogen Pseudomonas aeruginosa can participate in inter-species communication through signaling by cis-2-unsaturated fatty acids of the diffusible signal factor (DSF) family. Sensing these signals involves the histidine kinase PA1396 and leads to altered biofilm formation and increased tolerance to various antibiotics. Here, we show that the membrane-associated sensory input domain of PA1396 has five trans-membrane helices, two of which are required for DSF sensing. DSF binding is associated with enhanced auto-phosphorylation of PA1396 incorporated into liposomes. Further, we examined the ability of synthetic DSF analogues to modulate or inhibit PA1396 activity. Several of these analogues block the ability of DSF to trigger auto-phosphorylation and gene expression, whereas others act as inverse agonists reducing biofilm formation and antibiotic tolerance, both in vitro and in murine infection models. These analogues may thus represent lead compounds for novel adjuvants to improve the efficacy of existing antibiotics.


2017 ◽  
Vol 29 (3) ◽  
Author(s):  
Willem Santana ◽  
Bergman Thahar ◽  
Endah Mardiati ◽  
Jono Salim

Introduction: Power chains is the common device used in fixed orthodontic treatment. Force decay in power chains is a problem that can affect the teeth movement due to a continuous force cannot be maintained. Force decay in power chain can be affected by the use of alcohol-containing mouthwash or alcohol-free mouthwash. The objective of this study was to determine the effect of alcoholic-containing mouthwash, alcohol-free mouthwash, and artificial saliva towards the power chains force decay. Methods: This research was an experimental analytic laboratory in-vitro with the comparative approach. The sample in this study were 40 power chain, short A (SA); 40 power chain, short B (SB); 40 power chain, long A (LA); and 40 power chain, long B (LB), which divided into 5 groups that were consecutively exposed to the artificial saliva as control group; Minosep® with 0.1% of chlorhexidine gluconate; Listerine® with 0% of alcohol; Hexadol® with 9% of alcohol; and Listerine® with 26.9% of alcohol. The measurement of force decay was performed with digital force gauge on day 0, 1, 14, and 28. The statistical analysis was done by using the Wilcoxon and Mann-Whitney tests. Result: There was a significant difference (p<0.05) between the force decay of power chain that exposed to the alcohol-containing mouthwash, alcohol-free mouthwash, and the artificial saliva. Conclusion: The force decay level of power chain that exposed to an alcohol-containing mouthwash was higher compared to the force decay level of power chain that exposed to an alcohol-free mouthwash and an artificial saliva.


2018 ◽  
Vol 21 (1) ◽  
pp. 96 ◽  
Author(s):  
Tabata Prado Sato ◽  
Celio Ilidio Conjo ◽  
Rodnei Dennis Rossoni ◽  
Juliana Campos Junqueira ◽  
Renata Marques de Melo ◽  
...  

<p><strong>Objective: </strong>This study evaluated the effects of the incorporation of silver nanoparticles (AgNPs) obtained from <em>Fusarium oxysporum</em> on heat-activated acrylic resin (HAAR) and their influence on resin’s surface roughness, hardness, color alteration and antimicrobial capacity against <em>Candida albicans</em>. <strong>Material and Methods:</strong> For this, 50 discs of HAAR (2x5 mm) were produced and divided into three groups, Control: HAAR; Ag1: HAAR plus 0.539 mg of AgNPs; and Ag2: HAAR plus 1.1 mg of AgNPs. Knopp hardness (HK), surface roughness (Ra and Rz) and color alteration according to the CIE Lab were measured. Specimens were then evaluated <em>in vitro</em> with regard to <em>C. albicans</em> biofilm formation through formed colony count (CFU/mL). Scanning Electron Microscopy (SEM) and Atomic force microscopy (AFM) analyses were performed. <strong>Results:<em> </em></strong>The addition of AgNPs of both concentrations changed Ra, Rz and HK significantly. There was statistically significant difference for L (p=0.00); a*(p=0.00) and b*(p=0.00) parameters. There were no differences between Ag1 and Ag2 biofilm formation, but the comparison of both with the control group presented a significant reduction (p=0.0091) on biofilm formation. SEM and AFM images showed no signs of NPs clustering. <strong>Conclusion:</strong> It can be concluded tha AgNPs incorporation in HAAR was effective in reducing <em>C. albicans</em> activity, with a slight change in color and hardness of the material, being effective therefore, in regions such as the dental prostheses palate, which have lesser aesthetic appeal.</p><p><strong>Keywords</strong></p><p>Acrylic resins; Silver; Antimicrobial agents.</p>


Author(s):  
Ramazan Behzadi ◽  
Ahmad Hormati ◽  
Karim Eivaziatashbeik ◽  
Sajjad Ahmadpour ◽  
Fatemeh Khodadust ◽  
...  

Background: Anti-cancer activity of some lactic acid bacterial strains is well documented in several literatures. Lactobacillus strains have received considerable attention as a beneficial microbiota. The aim of this study is to evaluate the effects of anti-tumor activities of L. acidophilus ATCC4356 culture supernatants on the MCF-7 human breast cancer cells. Materials and methods: Anti-cancer effect of 24h and 48h culture supernatants at various concentrations (1.25, 2.5, 5, 10 and 20 µg/ml) were determined by various in vitro and in vivo assays including MTT, tumor volume measurement as well as 99mTc-MIBI biodistribution in MCF-7 tumor bearing nude mice and histopathology test. For evaluation of the related mechanism of action, quantitative PCR was conducted. Results: The 48h culture supernatants at 10 and 20 µg/ml exhibited significant in vitro inhibition of MCF-7 cell proliferation. However, this inhibition was not observed for HUVEC human endothelial normal cells. Q-PCR indicated that treatment by the supernatant led to a significant downregulation of VEGFR ( ̴ 0.009 fold) and Bcl-2 ( ̴ 0.5 fold) and upregulation of p53 ( ̴ 1.3 fold). In vivo study using MCF-7 xenograft mouse models demonstrated reduction in tumor weight and volume by both 24h and 48h supernatants (10 µg/ml and 20 µg/ml) after 15 days. According to the 99mTc-MIBI biodistribution result, treatment of MCF-7 bearing nude mice with both 24h and 48h supernatant (20 µg/ml) led to significant decrease in tumor uptake compared with the control group. Conclusion: These results suggest that the culture supernatants of L. acidophilus ATCC4356 at suitable concentrations can be considered as a good alternative nutraceutical with promising therapeutic indexes for breast cancer.


2021 ◽  
Author(s):  
Ladan Ranjbar Omrani ◽  
Saba Tohidkhah ◽  
Elham Ahmadi ◽  
Mahdi Abbasi ◽  
Reza Morvaridi Farimani

Abstract Background: The aim of the current study was to evaluate and compare the influence of Dycal, Lime-lite, Theracal LC, Biodentine, Resin-modified glass ionomer cement (RMGIC), and Activa Bioactive as the pulp capping material on the shear bond strength of resin composite to dentin.Methods: A total of 70 extracted caries-free molars were randomly assigned to seven groups. Six test groups were covered with various protective liners: Dycal (GD), Theracal LC (GT), lime-lite (GL), Activa Bioactive (GA), Biodentine (GB), RMGIC (GR). The control group (GC)received no liner pretreatment. Each sample was bonded to resin composite using the total-etch tetric N bond adhesive. The samples were then tested for shear bond strength using the universal testing machine at a cross-head speed of 1 mm/min until bond failure occurred. The data were analyzed using the one-way ANOVA test followed by the Tamhane post-hoc test for pairwise comparisons of the groupsResults: Independent of the type of the applied liner, all groups exhibited inferior SBS to dentine compared to the control group. GT and GR showed significantly higher shear bond strength than GB and GD, which showed the lowest shear bond strength. GL and GA also had significantly lower SBS results than GT. The mode of fracture was predominantly cohesive in GD, GB, and GT and adhesive in GA.Conclusion: This present study concludes that the bond strength of resin-composite to dentine can be affected differently using various types of liners.


Sign in / Sign up

Export Citation Format

Share Document