[Possibility of using microalgae Spirulina platensis powder in industrial production of Iranian traditional cookies]

There are a few studies about wheat flour fortification with powdered Spirulina platensis microalgae to produce industrial cookies. The objective of this study was to investigate the effects of Spirulina platensis microalgae used in production of traditional Iranian cookies on their nutritional value, color and texture. Samples of cookies were prepared using S. pirulina platensis at a level [% w/w] of 0.0, 0.5, 1.0 and 1.5%. The protein, iron and poluunsaturated fatty acid [PUFA] contents of the samples were measured by microkjeldahl, atomic absorption and GC mass chromatography, respectively; the peroxide value in the four samples was also determined. Sensory evaluation [hedonic scale 1-5] of the samples was made by 14 trained panelists. The iron, protein and gamma -linolenic acid contents of the fortified cookies were higher, and their peroxide value lower, than the respective control values. With regard to sensory evaluation, cookie samples containing 1.0% and 1.5% S. platensis scored highest following the control sample [p<0.05]. It is possible to produce cookies fortified with1.0-1.5% S. platensis with desirable nutritional and sensory characterstics

[Evaluation of effect of adding silica fillers to adhesive on microleakage of composite restorations in different times]

Dental adhesives are widely used in modern dentistry to provide retention of composite resin restoration and to reduce associated marginal microleakage. We aimed to evaluate the effect of adding silica fillers to adhesive on microleakage of composite restorations in different times. Forty-eight premolars were collected in 0.5% chloramine T solution. The teeth were divided into two groups. CLV cavities were prepared. In the first group, SE bond and in the second group, experimental unfilled SE bond were applied. In subgroups 1 of both groups, the teeth were incubated for 3 months then evaluated. In subgroups 2 of both groups, evaluation was performed after 24 hours. Cavities were filled with Z250 composite resin. Before incubation, samples were thermocycled at 5 to 55°C in 1000 cycles, then immersed in silver nitrate solution and afterwards developer solution for microleakage evaluation. They were then mounted, sectioned and observed under steriomicroscope and scanning electron microscope for scoring. The data were analyzed with Kruskal-Wallis and Mann-Whitney tests. There was significant difference in microleakage between groups in different times. There was no significant difference between occlusal microleakage regardless of time [p<0.001]. The difference between cervical microleakage of two adhesive types was not significant [p=0.533]. There was significant difference between 24 hours and 3 months storage [p<0.001]. No significant difference was detected between filled and unfilled adhesives regardless of time [p<0.001]. Although there was no significant difference between the two adhesives, unfilled adhesives performed slightly better than filled adhesives

[Production of selenium-enriched yeast using a Plackett-Burman design]

Today dietary deficiency of selenium [Se], an important mineral in human nutrition, is common in many regions and communities. Se-enriched yeast, obtainable by growing Saccharomyces cerevisiae in Se-rich media, is considered as a source of organic Se suitable for alleviating its deficiency due to its high bioavailability, stability, digestability, and absorbability. Using a Plackett-Burman design, the effects of various culture medium conditions, including temperature [28 and 30°C], initial pH [4.5 and 5.8], shaking speed [130 and 160 rpm], fermentation duration [24 and 48 h], size of inoculum [30 and 60 g/l], Se concentration [15 and 25 micro g/ml] and time of Se addition [0 and 9 h], on the bioaccumulation of Se in the yeast were investigated.. The Se content in the yeast was determined by graphite-furnace atomic-absorption spectroscopy. The results showed that Se concentration, size of inoculums, temperature, time of Se addition and fermentation duration were, in ascending order, the most significant factors on the yield of total Se accumulation and organic Se formation in the yeast. Manipulating these conditions/variables could markedly affect the magnitudes of incorporation of Se and formation of organic Se in the yeast, the ranges being 107.9 to 287.6 mg/kg and 93.27 to 269.05 mg/kg, respectively. The most suitable culture medium conditions to attain the highest level of total and organic selenium Se biotransformation in yeast are a concentration of 25 micro g/ml sodium selenite, an inoculum size of 30 g/l, a temperature of 28°C, an initial pH of 5.8, a shaking speed of 130 rpm, an incubation time of 48 h, and adding the selenium source to the culture medium 9 hours after the start of fermentation

[Effect of incubation temperature and inoculation ratio of starter culture on propionic acid production in dairy beverage fermented with propionibacterium]

Increasing trends of overweight and obesity prevalence have prompted food producers to develop products that can enhance satiety signals. The role of short-chain fatty acids as satiety-inducing triggers seems to be of interest in this regard. The objective of this research was to investigate the impact of two process variables, namely, incubation temperature and inoculation ratio of starter bacteria, on propionic acid production in the fermented dairy beverages containing Propionibacterium immediately after fermentation and during cold storage. Fermented dairy beverage [FDB] samples were prepared using mixed cultures of Lactobacillus acidophilus and Propionibacterium freudenreichii ssp. shermanii at a ratio of 1:2, 1:4 and 1:8, repectively, at incubation temperatures of 30, 35 and 40°C, until the pH reached 4.0 +/- 0.1. Propionic, lactic and acetic acid contents of the samples were measured immediately after fermentation using HPLC. The FBD samples were refrigerated for 28 days and the concentrations of the acids in the samples with the highest propionic acid content were measured. Sensory evaluation of the samples produced was made by 11 trained panelists using the hedonic scale. The maximum propionic acid content [w/w%] was observed in a mixed culture of L. acidophilus and P. freudenreichii ssp. shermanii at a ratio of 1:4 and an incubation temperature of 30 °C. It increased from 0.75 at day 0 to 1.2 at day 28 during storage at 4°C. The incubation temperature had a statistically significant inverse effect [P<0.05] on the propionic acid production in the fermented dairy beverages

[ 71 -year-old female with anthrax infection of eyelids]

Anthrax is an acute infection caused by the Bacillus anthracis a Gram-positive organism.cutaneous infection by anthrax is a rare condition. We report a case of anthrax as palpebral disease. A 71 -year-old female farmer, with anthrax infection of eyelids is presented. She was rural. She had a history of contact with animal and agricultural products. Additionally; she had a suspected history of insect bite. She treated with penicillin and ciprofloxacin. As this infectious is very contagious; early diagnosis is very important and prognostic. Thus, this form of disease should be considered in differential diagnosis of orbital cellulitis

Mycoprotein production by Fusarium venenatum in surface culture using a central composite design

Due to their nutritional, physical and chemical characteristics, mycoproteins, produced in the process of fungal growth, have been proposed to be used as a food additive for man. In this study a central composite design was applied to assessing the effect of seed size and initial concentrations of carbon and nitrogen sources on mycoprotein production by Fusarium venenatum [ATCC20334] from date sugar. Chemical composition [percent dried cell weight, nitrogen, moisture, and ash] and pH of the substrate were determined. Vogel culture medium was used for maintenance and inoculum preparation, and incubation was done at 30 °C for 72h. Dried cell weight was measured by the oven method. The experimental results were fitted to a full quadratic second order polynomial equation and the optimization of response was done with Minitab 14 software. Optimum conditions were determined and a confirmation test was conducted. The regression coefficient of the model presented for mycoprotein production [based on dried cell weight] was 98.0%. The optimum conditions for the mycoprotein production included a seed size of 15.39% v/v, and a carbon and nitrogen source of 20 and 4.35 g/L, respectively. The predicted value for the optimum production of dried biomass was 5.032 g/L. The reconfirmation test was conducted at the optimum conditions and the result obtained was 4.84 g/L of biomass production. The regression coefficient indicates accuracy and suitability of the model for the experimental data. By changing the inoculum conditions and the chemical composition of the culture medium, optimal growth of Fusarium venenatum and, consequently, maximum biomass production, can be achieved. Use of date syrup as an available and domestic Iranian substrate for modification of Vogel medium makes possible protein production at an industrial scale in surface culture

[Comparison of bench-scale production of xanthan by xanthomonas campestris in solid state and submerged fermentation]

Xanthan gum is an important natural biopolymer with numerous applications in various technologies, specially food industry. In this research, microbial production of xanthan by Xanthomonas campestris PTCC1473 from sugarcane molasses and date sugar in submerged fermentation [SmF] and also dried date waste [cake produced after pressing] in solid state fermentation [SSF] were compared. The Plackett-Burmann design [PBD] was used in this study. Chemical composition and characteristics [dried cell weight, nitrogen, moisture, ash and pH] of the substrates were determined. Yeast malt broth [YMB] and yeast malt agar [YMA] were used as maintenance and inoculum preparation media, and incubation was performed in a shaker incubator [at 28degreeC, 72 h and 200 rpm]. The fermentation medium was centrifuged at 5degreeC and 21055 multiplied by g for 50 minutes and the supernatant separated from the pellet for further xanthan extraction. After precipitation of xanthan by isopropanol, resuspension and further purification by centrifuge [at 2056 x g], the xanthan dry weight was determined. The effects of several variables, including the kind and concentration of carbon [date sugar and sugarcane molasses], nitrogen [ammonium nitrate and diammonium phosphate] and phosphorus [KH2PO4], temperature, shaking, and size and age of inoculum, on the yield were determined. The most effective variables were found to be the type of carbon and nitrogen sources in the medium. It can be concluded that both the yield [% w/w of xanthan/consumed sugar] and productivity [g/g.day xanthan/consumed sugar] are higher in SmF [22.4 and 7.46] than in SSF [13.3 and 4.43]. In addition, date extract results in a higher productivity than date waste and sugarcane molasses. The xanthan yield could be increased by changing the composition and physical conditions of the culture medium

Efficacy of QTH and LED light sources, in polymerization of dual cure resin cement beneath a simulated ceramic onlay

The dual cured resin cements are conventionally used for cementing indirect restorations, such as composite and ceramic inlays and onlays. The aim of this investigation was to evaluate the efficacy of two light-curing units, LED and QTH in polymerization of dual cured resin cement that were placed beneath the ceramic onlays. This experimental study was conducted using 20 specimens. Ten specimens were cured with QTH and the rest with LED light curing devises. Metal rings with 5mm in diameter and 0.5mm in thickness were placed next to the surface of the curved dentin of the molar teeth that were mounte4 in self cured acrylic resin. A Mylar strip was placed beneath the metal rings and they were filled with Maxcem dual cured resin cement; they were then covered with another Mylar strip. Next, the ceramic onlays with 2mm thickness were placed over the Mylar strips. The specimens were stored in a dry and dark incubator at 37°C for 24 hours, after cemented onlays were cured for 60 seconds. The Vickers hardness was determined for each sample and data were analyzed by using student T-test and SPSS statistical software. The mean Vickers hardness for QTH cured specimens was [24.75 +/- 3.59], and this value was [33.92 +/- 2.28] for the LED light cured specimens. The mean group difference was statistically significant [P < 0.001. Based on these findings, the efficacy of LED light curing unit was significantly more efficient in polymerization of resin cements that were placed underneath the ceramic onlays compared with QTH light-curing unit

Effect of salivary contamination on shear bond strength of composite resin used between teeth and brackets

Enamel contaminations with salivary proteins or blood are the major reasons for debonding of brackets. The purpose of this study was to evaluate shear bond strengths of bonded brackets with enamel surfaces under different conditions. The Concise composite [3M, Unitek] was used for adhesion of 0.018 inch standard brackets [3M, Unitek]. Fresh human saliva was used for contamination of enamel surfaces. 90 teeth were divided into 6 groups: 1- No surface contamination, 2- Contaminated after etching, 3- Contamination after application of bonding resin, 4- Contamination after etching, then re-etching, 5- Contamination after resin bond application, then re-etching and 6- Contamination after resin bond, then application of resin bond again. Surface contaminations were dried in all groups. After bracket bonding, the samples were held in distilled water in 37°C for 24 hours. Specimens were then thermo-cycled for 650 times at 5°-55°Centigrade. Shear bond strengths were measured by DARTEC machine. Data were evaluated by Duncan and variance analysis. Statistical analysis of data reveals significant differences only in groups one and four [P < 0.05]. The maximum shear bond strength was observed in the fifth group [21.61 +/- 2.6 MP] and the minimum in the third one. After salivary contamination of enamel, adequate clinical shear bond strength can be gained with drying of contaminated area and re-etching for 10 seconds. No washing is required in this case

Comparative evaluation of different methods of strengthening in endodontically treated maxillary central incisors with thin root walls

The structural rehabilitation of a pulpless tooth is critically important to ensure a successful restorative outcome following endodontic treatment. A post and core is often indicated for the retention and reinforcement of the final restoration. But, the clinical situation is significantly challenging if the root exhibits immature development or there is a thin root wall that can compromise the prognosis for a long-term successful treatment. The purpose of this in vitro study was to evaluate different methods of intraradicular reinforcement in structurally compromised roots. In this experimental study, seventy two extracted intact maxillary central incisors with similar size, shape and root anatomy were selected. After root canal therapy in 60 teeth, an acrylic laboratory bur was used to thin the cervical area and simulate the thin dentinal walls of immature teeth. The preparation was performed through the palatal access and extended 5mm apical to CEJ. The remaining 12 teeth remained unprepared to serve as positive control group. Cases were randomly divided into six groups of 12 teeth each and restored as follows. In the 12 cervically unprepared teeth [positive controls] the composite resin with dentin bonding agent [DBA] was placed in access cavity and cured for 120 seconds. This technique was also applied to other groups when the access was restored with composite. In the second group, the access cavity was restored with composite only to the level of CEJ. In the third group the cervically prepared teeth were reinforced with cement resin [Enforce] and a prefabricated post was placed in 5mm apical to the CEJ. In the fourth group, the cervically prepared teeth were reinforced with composite resin and DBA by a clear plastic post. In the fifth group the cervically prepared teeth were reinforced with composite resin and dba and a cast post. In the sixth group the cervically prepared teeth were restored with composite resin and dba with a prefabricated post. All of the specimens were mounted by rubberized technique arid tested in the Instron universal testing machine. The fracture loads in samples were analyzed with ANOVA and Duncan tests with p<0.05 as the limit of significance., Significant differences in fracture resistance were observed between the first and second groups compared with others. The highest fracture resistance values were recorded for first group while the lowest were registered for the second group. Fracture resistance of the third, fourth and fifth groups had no significant statistical differences with others and fracture resistance of sixth group was the highest with significant difference [P<0.05]. From this study, it may be concluded that the use of a dba and a composite resin in thin-walled roots reinforces the immature teeth and facilitates the use of post

[Microleakage of class V resin composite restorations using LED and QTH systems, in different light curing distances and time storages]

There is a principle rule about marginal seal in durability and clinical success of restorative treatments. Polymerization shrinkage and microleakage are critical limitations of dental composites. The aim of this study was to evaluate the effect of two different curing units on microleakage of class V composite restorations in different conditions. In this in vitro study, class V cavities were prepared on the buccal surfaces of 80 extracted premolar teeth. Conventional halogen curing unit [optilux 501] and high intensity light-emitting-diodes [LEDmetron] were used to polymerize resin composite [Z100] from two distance 2 and 8 mm. Four groups after 24 hours and the other four groups were restored for 3 months in water at 37 degree C, immersed in dye solution and then teeth were sectioned longitudinally and evaluated for dye penetration. Data were statistically analyzed using Kruskal-Wallis and Mann-Withney tests to compare the different groups. Using Kruskal Wallis test, no significant difference in microleakage was demonstrated between the different light cure units in the 8 groups. Mann-Whitney test at the dentin side showed that, QTH could significantly reduce the microleakage compared to LED [p=0.007]. Increase in distance and storage time did not influence the microleakage. At 2 mm distance, the difference between LED and QTH was significant [p=0.038], but no significant difference was seen at 8 mm distance. Increased distance for LED and QTH did not cause any microleakage. According to the results of this study, it can be concluded that the use of turbo light guide in LED would decreases the output of the light. Therefore, QTH system is recommended to be used in shallow cavities

Effect of pre-etching on sealing ability of two current of corrent self-etching adhesives

We evaluated the effect of phosphoric acid etching on microleakage of two current self-etching adhesives on enamel margins in comparison to a conventional total- etch system. Sixty buccal class V cavities were made at the cemento-enamel junction with beveled enamel margins of extracted human premolar teeth and randomly divided into five groups [12 specimens in each group]. Group 1 was applying with Clearfil SE bond, Group 2 with 35% phosphoric acid etching of enamel margins plus Clearfil SE bond, Group3 with I bond, Group 4 with 35% phosphoric acid etching of enamel margins plus I bond and Group 5 with Scotchbond multi-purpose. All groups restored with a composite resins. After 24 hours storage with 100% humidity, the samples were thermocycled, immersed in a dye solution and sectioned buccoligually and enamel margins microleakage were evaluated on a scale of 0 to 2. The differences between Groups 1 and 3 and Groups 3 and 4 were significant [P<0.05] but no significant differences between Groups1 and 2 or 1 and 5 were observed. The findings suggest that all-in-one adhesive systems need pre-etching enamel margins with phosphoric acid for effectively seal