Growth Optimization of Lactobacillus plantarum T5jq301796.1, an Iranian Indigenous Probiotic in Lab Scale Fermenter

Background and Objective: Lactobacillus plantarum is one of the probiotics species used in functional food products. These bacteria or their purified bacteriocins are used as biological preservatives in the food industry. The first step in production of an array of probiotic products is optimizing production in fermentors. This study aimed to examine factors affecting the in vitro growth optimization of Lactobacillus plantarum T5JQ301796.1 in a lab scale fermentor.Materials and Methods: Following 24 hours of anaerobic culture of the lactobacillus at 37°C, the pre-culture was ready and was inoculated to a 5 liter fermentor at 37°C and stirred at 40 rpm. Then factors affecting lactobacillus growth including carbon and nitrogen sources and pH were studied. The results were interpreted using response surface methodology (RSM), and optimal conditions for the equipment were determined.Results and Conclusion: For optimal growth of Lactobacillus plantarum T5JQ301796.1 in lab scale fermentor, the optimal conditions were 25.96 gl-1 of glucose, 1.82% of yeast extract, pH of 7.26, and stirring at 40 rpm at optimum temperature between 37-40°C. In this condition, maximum viable cell in the batch fermentation was 1.25×1010 CFU ml-1. Application of central composite design for the growth optimization of this bacterium led to maximum viable cells equal to 1.25×1010 CFU ml-1. So the mentioned features can lead to optimum industrial scale production and usage of this probiotic strain in probiotic products.Conflict of interest: The authors declare that there is no conflict of interest

Management of a Large Periapical Lesion Using Decompression: A Case Report with Three-year Follow-up

Large radicular lesions should be treated initially by orthograde root canal therapy. When the signs and symptoms of the infection (e.g. persistent purulent drainage) do not resolve after this treatment, then surgical approaches should be considered. In the cases of large radicular cysts, total enucleation of the cyst can endanger adjacent structures and teeth. Therefore, decompression or marsupialization techniques are recommended in order to decrease the size of the lesion. In this case report, a 55-year-old woman with previously initiated therapy was referred to endodontic department for management of a sinus tract associated with tooth #7. Root canal treatment was performed and intracanal irrigant (5.25% sodium hypochlorite) activated using passive ultrasonic application, various intracanal medicament (calcium hydroxide, double antibiotic paste) was used in multiple sessions, but intracanal purulent drainage was not resolved. After this, decompression was performed using needle cap to maintain the opening of the cyst and remained for three months. During this period the cavity was kept clean and rinsed by the patient with 0.2% chlorhexidine mouthwash. After three-year follow-up, radiographic examination revealed substantial osseous repair of the defect and clinical signs and symptoms were absent

Comparison of the Antibacterial Effect of AH26, Adseal and Beta RCS Root Canal Sealers Against Enterococcus Faecalis, an in Vitro Study

Objectives: Antibacterial activity against endodontic pathogens is a desirable feature for root canal sealers. The objective of this study was to compare the antibacterial effect of three resin-based endodontic sealers (AH26, Adseal, and Beta RCS) against Enterococcus faecalis in vitro. Materials and Methods: The antibacterial properties of the sealers were assessed against E. faecalis using agar diffusion test (ADT) for fresh state (N=10) and direct contact test (DCT) for freshly-mixed and set states of the materials (N=10). In ADT, the diameter of the zones of inhibition was measured after 24h of contact. In DCT, the colony-forming units of the bacteria were counted after 30 minutes and 180 minutes of exposure. The results were analyzed with two-way ANOVA and independent sample t-test. P<0.05 was considered significant. Results: Regarding DCT results, all test materials indicated an antibacterial effect, both in freshly-mixed and set states. The highest antibacterial effect was related to Adseal, whereas the lowest was observed in Beta RCS. There was a significant difference between all study groups (different sealers, setting states, and contact times; P0.05). According to ADT, AH26 and Adseal represented the widest and the smallest inhibition zones, respectively (P<0.001). Conclusion: Within the limitations of this in vitro study, AH26, Adseal, and Beta RCS showed antibacterial effects against E. faecalis in both freshly-mixed and set states. The antibacterial effect increased over time in all of the studied sealers