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The aim of this study was to investigate a possible relation between EPS production and resistance to bile salts and tolerance to low pH. Eight strains which produced the highest and lowest amount of EPS (16- 211mg/l) were selected among 54 bacteria isolated from yogurt. Additionally, they were tested for resistance to bile salts (0.15, 0.3 %) and tolerance to low pH (2.0-3.0). After treatment with bile salts and acid, viable bacteria (log cfu ml-1) were determined by surface plating. The high EPS producing strains (B3, G12, W22) showed a significant (P<0.05) protective effect against low pH (pH 2.0). All Streptococcus thermophilus strains showed a higher tolerance to bile salts than the Lactobacillus delbrueckii subsp. bulgaricus strains. The high EPS-producing S. thermophilus (W22, T12) and L. bulgaricus (B3, G2) strains showed a significant (P<0.01) protective effect against bile salts (0.3 %)

It is believed that an important criterion for a potential probiotic strain is that it is capable of adhering to mucosal surfaces in the human gastrointestinal tract. The purpose of this study was to investigate a possible relationship between exopolysaccharide production and adhesion to Caco-2 cells by Bifidobacterium breve A28 and Bifidobacterium bifidum A10. In a preselection process, the hemagglutination abilities of these bacteria were determined prior to undertaking adhesion studies. B. breve A28, which produces large amounts of EPS (97.00 ± 2.00 mg/l) and has good hemagglutination abilities (+3) was found to adhere strongly to Caco-2 cells. Under gastrointestinal conditions, the high EPS producing-B. breve A28 was found to have better viability and adhesion to Caco-2 cells than the low EPS producing-B. bifidum A10. Also, B. breve A28 was found to be more effective at inhibiting Escherichia coli ATCC 11229 than B. bifidum A10. This investigation showed that high EPS production and adhesion ability may be important in the selection of bifidobacteria as probiotic strains.

Background/purpose: Cariogram is a software program which was recently developed for the practical application of caries-risk assessment. The purpose of this study was to evaluate the relationships between caries risk and different variables of Cariogram in a young adult population. Materials and methods: This study included 90 volunteers (49 females and 41 males) aged 19e 25 years. Systemic diseases, diet frequency, fluoride programs, and the decayed, missing, and filled teeth (DMFT), decayed, missing, and filled surfaces (DMFS), and plaque indices were recorded by clinic and radiographic examinations. The saliva secretion rate, and Streptococcus mutans and Lactobacillus counts were determined by saliva sampling. Results: Statistically significant correlations were found between the caries risk determined by Cariogram and the past caries experience (DMFT and DMFS indices), fluoride programs, and S. mutans and Lactobacillus counts in the saliva. The results of a linear regression analysis showed that the most important factors for caries risk were the past caries experience, diet frequency, fluoride program, saliva secretion rate, and S. mutans and Lactobacillus counts. Conclusions: According to the results of this study, the most important factors for caries risk were the past caries experience, fluoride programs, and S. mutans and Lactobacillus counts Journal of Dental Sciences (2012) 7, 99e104 in saliva. Cariogram is a helpful method for dentists in clinical practice to assess caries risk, and it can be used as a didactic tool for patient education and motivation.

The aim of present work was the determination of antioxidant activities of the ethanol extract from three mushrooms (Ganoderma lucidium, Lentinula edodes and Coprinus micaceus) by using DPPH radical scavenging and total antioxidant status assays. Additionally, in this study, GC/MS analyses and antimicrobial activity assay of three mushrooms were made. Ethanol, chloroform and distilled water used as solvent for preparation of mushrooms extract. Radical scavenging activities and total antioxidant status of three mushrooms extracted in ethanol were measured via spectrophotometric methods. In addition, for chromatographic analysis GC/MS were used. At the same time, diphenic acid and bis(2-ethylhexyl)pthalate derivatives were found the highest in contents of all extracts with GC/MS. The determination of antimicrobial activity of mushrooms extracts against Pseudomonas aeroginosa (ATCC 27853), Escherichia coli (ATCC 25922), Enterococcus faecalis (ATCC 29212), Staphylococcus aureus (ATCC 25923) and Candida albicans (ATCC 10231) was investigated by disc and agar-well diffusion methods. As result, radical scavenging activities and total antioxidant status values of G. lucidium extract were found higher than those of both L. edodes and C. micaceus. All mushrooms used in this study were found to have antimicrobial effects at a variety of degrees against microorganisms tested. Moreover, all extracts together with solvents were analyzed, ethanol and chloroform extracts were found to be more effective for G. lucidum and C. micaceus, and L. edodes than other solvents, respectively.

In this study, the viability of free and immobilized forms of Streptococcus thermophilus A21 and W22 was evaluated in terms of their tolerance of low pH, bile salts and resistance to nisin and penicillin G. The immobilized strains were more resistant to low pH and to bile salts than free strains. Besides, immobilized strains found resistant to nisin and penicillin-G. When compared the amount of L(+) lactic acid and EPS produced by both free and immobilized strains, the decrease of L(+) lactic acid and EPS production in the immobilized strains were found to be insignificant. However, during a two week's storage period at refrigerator and room temperature, there were no significant differences in the viability of immobilized A21 and W22 strains. The results of this research show immobilization of the cells did not impair, or even improved, the probiotic and technological properties of tested strains.

Invertase (β-fructofuranoside fructohydrolase, EC 3.2.1.26) is an enzyme widely used in the food industry. Its main function is the formation of glucose and fructose through hydrolysis of sucrose. For the separation and purification of this commercially important enzyme from aqueous solutions, magnetic poly(2-hydroxyethyl methacrylate-N-methacryloyl-L-tryptophan), m-poly(HEMA-MATrp) microparticles were developed. Magnetic properties of microparticles are provided using ferromagnetic Fe(II)-Co(II) double salt. Characterization studies of magnetic microparticles were conducted via vibrating sample magnetometer (VSM), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) analysis. Specific surface area of magnetic microparticles is 6.75 m(2)/g. Because of all experiments performed in this study, the adsorption capability of magnetic microparticles was optimized by variation of different conditions (pH, interaction time, initial invertase concentration, temperature, and ionic strength) and maximum adsorption capacity was determined as 992.64 mg invertase/g magnetic microparticles.

M ushrooms play an important role in the carbonnitrogen cycle by breaking down organic substance in nature [1]. In addition to its existence for centuries, fungi have been used as nutritious food in daily meal and therapeutic agent in medicine because they are rich in protein, vitamins, and minerals [2].Auricularia polytricha is a macrofungus that is a member of Basidiomycota class and belongs to Auriculariaceae family [3]. They grow in Asia, tropical America, and other regions of the world [4]. The spread of fungal spores of A. polytricha are present in high amount during late July [5]. Culturing of this fungus is not difficult but slow like some other fungi [6]. A. polytricha is edible mushroom.