Search

Background: Electrochemical disinfection of the root canal system (RCS) is introduced as an alternative to conventional irrigation. The aim of this study was to assess the efficacy of depotphoresis method in the disinfection of accessible and inaccessible RCSs. Materials and Methods: In this comparative in vitro study disinfection of Enterococcus faecalis infected RCS using two methods, (1) depotphoresis and (2) sodium hypochlorite (NaOCl) irrigation plus passive ultrasonic agitation (PUA) took place on 40 extracted maxillary anterior teeth. Decoronation was done with a diamond disc, and the canals were instrumented. The roots were divided into two phases: the specimens with canal obstruction and the specimens without canal obstruction. The smear layer was removed, and the specimens were infected for 21 days with E. faecalis. After disinfection procedures, bacterial samples were taken using two sterile #35 paper points, and colony forming units (CFU) were counted. Data were analyzed statistically using the Kruskal--Wallis test, with a significance level at P < 0.05, to indicate differences between depotphoresis and NaOCl plus PUA groups. Results: In both phases, Log CFU after depotphoresis treatment was significantly lower than NaOCl irrigation plus PUA treatment (P < 0.05). Conclusion: Treatment with depotphoresis was significantly more effective than NaOCl irrigation plus PUA treatment. [ABSTRACT FROM AUTHOR]

Summary: In this study, poly (ether sulfone) (PES)/polystyrene (PS) thermoplastic polymer blend miscibility was looked at using both molecular dynamics (MD) simulations and experiments. In particular, the parameters of the Flory-Huggins interaction and the heat of mixing of poly (ether sulfone) (PES)/polystyrene (PS) blends at different compositions were calculated from MD simulation. For the PES/PS blend, both differential scanning calorimetry (DSC) and MD simulation showed that they are immiscible at PES/PS: 80/20,60/40 ratios. The degree of compatibility of the 20/80 and 40/60 PES/PS blends is higher than that of a PES-rich blend. This thermodynamic behavior was found to be due mainly to intermolecular interactions. Scanning electron microscopy (SEM) results confirmed this observation. Results show that the calculated greater than value is positive at the compositions of PES/PS: 80/20 and 60/40, which confirmed that the polymer mixtures were immiscible at these compositions. The miscibility between PES and PS at these ratios is attributed to favorable van der Waals interactions. Also, the results of the DREIDING 2.21 force field show that electrostatic energy, bond angle bending energy, and bond stretching energy may be to blame for the immiscibility of certain composition polymer blends (PES/PS: 80/20 and 60/40). [ABSTRACT FROM AUTHOR]

Astaxanthin and β-Carotene are wellknown carotenoids globally, covering more than half of the market demand for carotenoids. Haematococcus pluvialis microalgae are one of the most important sources of natural astaxanthin, consisting of up to 4% of its dry weight. The most critical challenge for this microalgae is the breakdown of the wall and the extraction of the pigment. In this study, chemical methods, including acid, acetone, and ionic solution, and physical processes such as ultrasound waves and magnetic stirrer, were used to break down the cell wall and meas-ure total astaxanthin in H. pluvialis, respectively. Due to the rapid oxidation of the pigment, in the next step, to extract and store astaxanthin from damaged cells, use olive oil. A spectrophotometer examined astaxanthin, monoester, and diester derivatives, and their amount was determined by thin layer chromatography (TLC) and high performance liquid chromatography (HPLC). The results showed that using acid treatment, ultrasound waves, and extraction by acetone is the best method to measure the amount of astaxanthin in the algae. The HPLC results also showed that the amount of astaxanthin monoester (88.44%) was higher than the free forms (3.76%) and diester (7.82%) in the total content of extracted astaxanthin. In addition, the amount of total astaxanthin in the H. pluvialis was about 1.6% of the dry weight of the algae. [ABSTRACT FROM AUTHOR]

In this study, the dominant lactic acid bacteria (LAB) in pickled garlic were identified by biochemical tests and a PCR technique. The LAB isolates were used as the starter culture in the fermented olive, in order to produce the fermented olive with probiotic potential, longer shelf life, and faster fermentation process. To determine the probiotic potential of the isolates, confirmatory tests were performed. Based on the BLAST results, five isolates of Lactobacillus plantarum, two isolates of Pediococcus ethanolidurans and one isolate of Lactobacillus brevis were identified. The LAB strains isolated in this study have had the survival ability at pH 2.5, antimicrobial activity against some pathogens, growing in the medium containing 0.3% bile salt, sensitivity to antibiotics, and without hemolytic activity, and therefore recognized as probiotics. The treatments with the starter culture of L. plantarum have had the lowest pH and the highest lactic acid content. In the sensory evaluation, these treatments had higher desirability and were significantly different from the control. [ABSTRACT FROM AUTHOR]

The present paper studies antibacterial activity (AA) and anti-enterotoxigenic activity (AEA) of three Iranian medicinal plant extracts, Origanum majorana, Areca, and Long pepper. In addition, the anti-enterotoxigenic interactive effects of these extracts as herbal extract blend (HEB) were studied. Kirby-Bauer, agar dilution, and Real-time PCR methods were used to study the AA and AEA of the extracts. The statistical method of mixture design was used to optimize and find out the best HEB with the highest AEA on A and B enterotoxins of S. aureus. In individual AA study of extracts, O. majorana extract had the highest AA. Among the extracts evaluated in this study, the extract of O. majorana had much AA on S. aureus and its enterotoxins production. As an interesting result, there is an inhibitory synergistic effect between the extracts studied in this paper on gene expression of sea and seb. The maximum AEA was observed by treat with HEB including 47% O. majorana, 26% Areca, and 27% Long pepper. [ABSTRACT FROM AUTHOR]

Purpose – Since a sound detoxification method is needed for controlling aflatoxin B1 (AFB1), as one of the most harmful mycotoxins in animal production and food industry, this study was performed. The paper aims to discuss these issues. Design/methodology/approach – This study was conducted to examine the ability of Lactobacillus rhamnosus strain GG to remove AFB1 from liquid media. The binding of AFB1 to Lb. rhamnosusGG was studied for viable, heat-killed and acid-killed bacteria. AFB1 at concentrations (5, 10 and 20 μg/l) was added to the bacterial culture (109 cfu/ml) in MRS broth medium and incubated at 25°C for 4, 12 and 24 h. The aflatoxin-binding capacity of the strain was quantified by the amount of unbound AFB1 using ELISA technique. Findings – Results showed the AFB1-binding capacity of viable, heat-killed and acid-killed bacteria was about 43, 49 and 50 percent, respectively. The percentage of AFB1 removed was the highest amount in low (5 μg/l) and high (20 μg/l) concentrations, and there was no significant difference between them (p=0.05). These findings suggest that lactic acid bacteria can be exploited as an approach to detoxification of aflatoxins from foods. Practical implications – This method is safe because non-viable bacteria have more ability to remove toxin than viable bacteria, and also it is an effective method with 50 percent approximately toxin removal. Originality/value – Since there has been no research on the ability of this strain on the removal of AFB1, the authors assessed the ability of the strain in high levels of AFB1. [ABSTRACT FROM AUTHOR]