Hyaluronidase has a panoramic use in biotechnology processes and therapy due to its therapeutic, pathophysiological, physiological and biological importance. Since much of the preparations of hyaluronidases are from animal source (bovine and ovine testicular sources) with limited sources of microbial origin, that prompted the authors to screen and isolate a new promising bacterial strain with higher yield followed by its characterization employing detailed taxonomic studies. The newly isolated strain was identified based upon their micro- and macro-morphological, cultural, physiological and biochemical parameters. Twenty isolates from different pathological samples were primarily selected and further screened for their hyaluronidase producing capabilities by measuring reduction in turbidity and hydrolyzed zone of substrate hyaluronic acid. Four isolates showing marked reduction in turbidity (A600 nm) and hydrolyzed zones were selected and subjected to secondary screening by shake flask fermentation. Isolate SII9 (Dental caries specimen) exhibited maximum hyaluronidase activity (117 U/ml) when compared to the reference Streptococcus mitis MTCC*2695 (106 U/ml). A close scrutiny of the literature revealed that the characteristics of our isolate SII9 are mostly identical to S. equi subsp. equisimilis with few differences and thus designated as S. equi SED 9.

Introduction: Bacterial plaque is the most common etiology of oral conditions such as dental caries, gingivitis and periodontal disease. One of the most common periodontal diseases is gingivitis. Elimination of bacterial plaque is the main goal in treatment of this destructive inflammatory disease. The purpose of this study was to investigate the prevalence of Streptococcus mitis in bacterial plaque and its sensitivity to b-lactam antibiotics.Materials and Methods: In this cross sectional study, we evaluated the effectiveness of 10 b-lactam antibiotics for the treatment of gingivitis via determining the antimicrobial susceptibility of the major pathogens. This study included 100 patients referring to Oral Disease Department at the School of Densitry, Isfahan University of Medical Sciences, from 2003 to 2004. Sampling of plaques on the cervical region of anterior teeth was performed with periodontal probes. Samples were then cultured into chocolate and blood agar media. In this study a total of 361 types of bacteria were isolated. Isolated strains were identified through biochemical tests. The antimicrobial susceptibility of Streptococcus mitis to 10 b-lactam antibiotics was assessed by Disk plate and Kerby-Bauer. The collected data were analyzed via t-test on a computer using SPSS (a=0.05).Results: The results showed that there were 204 Streptococcus strains (55.9%). Streptococcus mitis formed 12.93%. The sensitivity of Streptococcus mitis to b-lactam antibiotics was more than 80% except for penicillin and ampicillin. As much as 2% of strains were sensitive to clindamycin.Conclusion: Streptococcus mitis in the dental plaques seem to be sensitive to b-lactam antibiotics.Therefore such antibiotics might be considered for the treatment of gingivitis.

Due to the increased resistance to antibiotics and chemical biocides, the use of bacterial exopolysaccharides has been considered. The objective of the current study was to investigate the strength of the antibacterial and antibiofilm activity of EPS extracted from Lactobacillus reuteri and Streptococcus mitis because previous studies showed there were structural differences between EPS, during this study, EPS extracted from Lactobacillus reuteri and Streptococcus miti by ethanol precipitation method and estimated antibacterial and antibiofilm activity against several Oral Bacteria (Staphylococcus aureus, Staphylococcus hominis, Acinetobacter baumannii, Raoultella ornithinolytica, Streptococcus thoraltensis in different concentration as (100, 150, 200, 250, 300 mg/ml ), the results showed carbohydrates rate in extracted EPS from L. reuteri and S. mitis were recorded was 85, 80 % respectively. The concentration 100 and 150 mg/ml for EPS from L. reuteri and S. mitis, there was no inhibitory effect, except in S. aureus (1. 1±, 0. 10) and S. hominis (1. 0±, 0. 10) at 100 mg/ml, 3. 1±, 2. 01, 2. 1±, 0. 54 mg/ml respectively at 150 mg/ml concentration but no significant differences (P≤, 0. 05). However, the antibacterial effect of that EPSs started at the concentration of 200 and upwards, where different results were recorded between the concentrations of both EPSs against all bacteria isolated (P≤, 0. 05), On the other hand, the effect of EPS from L. reuteri and S. mitis was clear against the formation of biofilm compared with the control, worth mentioning that EPS from L. reuteri was more effective compared with EPS from S. mitis in all isolates (P≤, 0. 05) except for S. thoraltensis where it was noted that the EPS from S. mitis is more effective than EPS from L. reuteri. Through the results obtained in this study, it was noted that the difference in the structural nature of EPS has an important role in its effectiveness as an antibacterial and antibiofilm formation and, as it was found that the EPS from L. reuteri showed more effectiveness than EPS from S. mitis and thus the mechanism of preventing and inhibiting bacteria depending of the structural nature of EPS.

Background & Objectives: Turbidity and colloidal factors are good shelters for growth and transmission of biological parameters as well as the factors affecting water usage from aesthetic point of view. Coagulating agents such as metal hydroxides are produced by the process of electrolysis. The coagulating agent combines with the pollutants to form large size flocs. This study aimed to investigate the efficiency of electrocoagulation-electrofloatation in removal of turbidity from aquatic environments.Methods: In a laboratory-scale fundamental-applicable study a plexiglass electrocoagulation reactor (24×17×18 cm) was made.4 iron/aluminum plates (electrode) with a dimension of 15 ×16 cm and thickness of 1mm were placed in parallel and 1.5 cm apart in the tank. A DC power supply with adjustable voltage (0-60 v) and amperage (0-6 amps) was used.Results:: The results showed that the highest turbidity removal from solution was obtained by aluminum electrode (97.60%) at pH of 7, potential difference of 50 volts, and contact time of 30 minutes. The maximum rate of turbidity removal from aqueous solution by using iron electrodes (89.92%) was achieved at pH=7, potential difference of 50 volts, and contact time of 30 minutes.Conclusion: based on experiments’ results, using electrocoagulation-electrofloatation has an appropriate efficiency in turbidity removal. It can also be concluded that the efficiency of Al electrode to remove turbidity from solution is higher than that of Fe electrode.

Objective(s): The present study aimed to investigate the antibacterial properties of a conventional epoxybased dental sealer modified with synthesized bioactive glass (BG), hydroxyapatite (HA), and fluorinesubstituted hydroxyapatite (FHA) nano-fillers. Materials and Methods: The synthesized nano-fillers were incorporated into the conventional epoxy-based dental seaer at the concentration of 10%. The antimicrobial properties of the unmodified sealers (controls) and modified sealers with BG, HA, and FHA nanoparticles (NPs) were evaluated based on biofilm formation and using the direct contact test (DCT) of Enterococcus faecalis and Streptococcus mitis. Data analysis was performed using one-way analysis of variance (ANOVA) and Tukey’ s post-hoc test at the significance level of 5%. Results: A significant reduction was observed in the biofilm formation and DCT of the microbial strains in the three modified groups compared to the unmodified conventional epoxy sealer (P<0. 05). The addition of FHA NPs resulted in the most significant antibacterial effects against E. faecalis and S. mitis, as well as a statistically significant reduction compared to the unmodified and BG-modified groups (P≤ 0. 001). Conclusion: According to the results of this preliminary study, nano-structured FHA, HA, and BG fillers incorporated into epoxy-based dental sealers could be potentially effective biomaterials for antibacterial approaches to root canal treatments.

Background and objectives: Streptococcus pneumoniae, a major human pathogen, is closely related to the commensal species S. mitis and S. oralis. S. pneumoniae surface proteins are implicated in virulence and host interaction of this species, but many of them have recently been detected in S. mitis B6 in silico. We tested for the presence of such genes usinga set of eight S. mitis and eleven S. oralis strains from different geographic locations.Materials and Methods: An oligonucleotide microarray was designed based on the genomes of S. pneumoniae R6 and TIGR4 as well as S. mitis B6 to include 63 cell surface proteins. The S. pneumoniae genes encoding neuraminidases, hyaluronidase and pneumolysin were also included. In addition to comparative genomic hybridization experiments, homologues were identified in silico in the genome of S. oralis Uo5.Results and Conclusions: The results document that many S. pneumoniae related surface proteins are ubiquitously present among the Mitis group of streptococci. All 19 samples hybridized with the pavA probe representing a gene important for adherence and invasion of S. pneumoniae. Only eight genes were not recognized in any strain, including the S. pneumoniae PcpC gene as the only virulence gene of the S. pneumoniae core genome. The fact that only 12 out of 26 genes present in the S. oralis Uo5 genome could be detected by microarray analysis confirms the sequence variation of surface components.

Objective: In-time diagnosis of Streptococcus pneumoniae (S. pneumonia) can play a significant role in decreasing morbidity and mortality rate. Applying molecular methods has gained popularity due to the existing limits of routine diagnostic methods. Examining the expression of different genes of this bacterium through different molecular methods suggests that lytA gene has a higher sensitivity and specificity in diagnosis of Streptococcus pneumoniae. The aim of this study was to evalutate lytA gene expression in diagnosis of invasive S. pneumonia in culture positive specimens by real-time polymerase chain reaction (PCR).Materials and Methods: IIn this a descriptive study, All received specimens were isolated to identify S. pneumoniae. DNA was then extracted and after optimizing the test and determining the detection limit, samples were tested by real-time PCR using lytA gene primers.Results: Twenty seven isolates were diagnosed as S. pneumoniae. In all, the extracted DNA was positive in real-time method. The electrophoresis of the products also confirmed the presence of single product b along with the 53 base pair fragment. The detection limit of the test was less 6 colony forming unit (CFU).Conclusion: Real-Time PCR seems to provide reliable and rapid results. We suggest that this test should be conducted on the preliminary isolated specimens, since applying various biochemical tests need one extra working day.

The goal of this study was to evaluate tannic acid as a coagulant in turbidity removal. Tests were designed using Taguchi method and carried out on the synthetic and natural turbid samples. In order to optimize turbidity removal by tannic acid, seven factors including pH, coagulant dosage, rapid mixing rate, slow mixing rate, slow mixing time, sedimentation time and initial turbidity were investigated. The results revealed that in optimum conditions, tannic acid could n remove up to 71 percent of synthetic turbidity and 66 percent of natural turbidity; also, tannic acid showed more coagulation activity in the lower initial turbidities. ANOVA analysis showed that initial turbidity and slow mixing time were the most important parameters in the turbidity removal by tannic acid. In general, this study showed that tannic acid was capable of removing turbidity and could be used instead of common coagulants in the preliminary treatment.

Background and Objectives: In recent years, increasing attention to the health and quality of food products has led to the importance of food processing using new methods. One of the significant challenges in this field is the turbidity of fruit juices, particularly red berry juice. An effective way to reduce turbidity is by using natural absorbents. In this regard, banana peel is introduced as a natural absorbent that can significantly contribute to the reduction of turbidity in red mulberry juice. Known for its rich compounds, including pectin and plant fibers, banana peel is recognized as a potential source for absorbing suspended particles and reducing turbidity.Materials and Methods: The primary materials studied in this research are red berry juice and banana peel. The berry juice prepared for this research had a Brix value of approximately 78, which was reduced using distilled water through a series of 15 dilutions. The banana peel was dried at a mild temperature of 45 oC in a laboratory oven and then ground to a uniform size of 1 mm using industrial sieves. The study compared neural network and factorial methods for reducing the turbidity of red mulberry juice with the natural absorbent of banana peel. The independent variables considered included temperature, time, and stirrer speed, each investigated at four different levels, with the experimental design employing a factorial approach. The responses measured were the percentage reduction in turbidity and the percentage reduction in absorbent efficiency.Results: The results showed that the maximum reduction in turbidity (47.22%) with the lowest reduction in the efficiency of the natural absorbent (57.65%) was achieved at a temperature of 30 oC, with surface absorption duration of 3 hours and a stirring speed of 300 rpm. Additionally, a neural network was utilized to predict the two dependent variables as functions of the independent variables. The neural network modeling demonstrated high accuracy in predicting the target variables, with mean relative error (MRE) values of 2.06% and 0.90% for the turbidity reduction percentage and the absorbent efficiency reduction percentage, respectively. In contrast, the factorial method yielded MRE values of 4.58% and 6.04%, thus significantly enhancing the prediction accuracy for the two dependent variables. Conclusion: Banana peel, as a natural absorbent, was effective in reducing the turbidity of red mulberry juice. Furthermore, the factorial method proved to be effective as one of the experimental design approaches for identifying optimal operating conditions in the turbidity reduction process. The use of a neural network for predicting the results of laboratory research demonstrated a high degree of confidence in modeling outputs. In this study, the neural network provided improved predictions for the two dependent responses, leading to enhanced outcomes in both turbidity reduction and absorbent efficiency reduction.