• Journal of Digital Convergence
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• v.11 no.12
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• pp.515-522
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• 2013

The purpose of this study was to closely examine the inhibitive effect of erythritol on growth and acidogenic ability of Streptococcus mutans. As expected, the growth of S. mutans was comparably increased with the addition of sucrose. However, xylitol and erythritol remarkably reduced the growth of S. mutans. Growth inhibition was detected at more than 5% of erythritol although xylitol showed growth inhibition effect at all concentrations tested. Growth inhibition effect was monitored with the combination of same concentration of erythritol and other carbohydrates. Combination of 5% or 10% erythritol with xylitol showed effective growth inhibition. Addition of 2.5%, 5%, or 10% erythritol with sorbitol also showed growth inhibition. From these results, erythritol showed potency of growth inhibition of S. mutans, which is involved in dental caries, and was confirmed to be an excellent sugar substitute, which has effect on preventing caries.

• Journal of dental hygiene science
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• v.12 no.4
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• pp.303-309
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• 2012

This study was designed to provide basic data for developing a standardized caries potentiality index to help to choose snack foods with a low score on the index by investigating adolescents' snack intakes and measuring them in total saccharinity, pH, and acidogenic potential and glucosidase activity of Streptococcus mutans (S. mutans). Total 28 snack foods were selected and measured for total saccharinity (Pocket refractometer PAL-1, ATAGO) and pH with a pH meter (Mentor, Seoul, Korea). Artificial saliva was added to each sample. The experiment group was administered with S. mutans (ATCC 3692), cultured in a constant temperature incubator at $37^{\circ}C$, and measured for pH changes over five times including after 10 minutes, 30 minutes, 1 hour, and 24 hours. Each sample of 0.3 ml was added to tubes containing sucrose, galactose, or glucose to measure the glucosidase activity of S. mutans. They were then observed for glucosidase activity with colorimetry after 24 hours of culture in a constant temperature incubator at $37^{\circ}C$. The mean pH by the acidogenic potential of S. mutans was pH 5.33. The experiment group dropped in pH more than the control group due to the increasing acidogenic potential of S. mutans by glucosidase activity, recording pH 5.27 after 10 minutes, pH 5.21 after 30 minutes, pH 5.15 after 1 hour, and pH 4.80 after 24 hours. The observation results of glucosidase activity of S. mutans with colorimetry show that most of the samples were positive in orange and yellow with glucose, sucrose, and glactose recording activity of 78.58%, 75%, and 71.42%, respectively.

• Journal of the korean academy of Pediatric Dentistry
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• v.36 no.3
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• pp.358-366
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• 2009

Lactic acid bacteria worked positively on gastrointestinal tract and oral environment. So I selected commercial five fermented milks and milk, and then I evaluated their effect of growth inhibition and biofilm formation of cariogenic bacteria, Streptococcus mutans. And also calculated the acidity, buffering capacity, concentration of Ca and P ion and pH change of those drinks. After adding S. mutans to fermented milks viable cell count of S. mutans in milk was not statistically different but those in all fermented milks were decreased as concentration of fermented milk increased. When I measured the amount of formed biofilm in 10% fermented milks and milk with S. mutans and compared with those without S. mutans, the amount was decreased in Active GG and Bulgaris while being increased in Tootee, Ace and milk(P<0.05). The fermented milk with the lowest pH value was E5(3.48${\pm}$0.01), and the highest was Bulgaris(4.19${\pm}$0.02). pH change of the fermented milks and milk with S. mutans was measured. The highest acid producing fermented milk was Bulgaris, and followed by Active GG, Ace, Tootee, E5, Milk. These results indicated that fermented milks had caries activity due to the value of initial acidity and acid producing capacity. But, concentrated fermented milks had the inhibitory effect against S. mutans, and also had high volume of Ca and P ion that protected teeth. So I suggest that they have positive effect on teeth.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.1
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• pp.123-128
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• 1996

저온저장 중 품질 열화가 일어난 단감의 산업적 이용성을 증진하기 위한 감식초의 가공조건을 조사한 결과, 연화된 단감을 폐쇄하여 종초 10%와 알코올 4%를 첨가한 후 발효온도 3$0^{\circ}C$에서 2주 이내에 산도 4%이 상인 감식초가 발효되었으며, 15$^{\circ}C$에서 3주간의 숙성 조건에서 식초 고유의 향미가 형성된 반면 포도당과 초산의 첨가는 최종 제춤의 품질을 저하시키는 결과를 얻었다. 연화된 단감의 열처리 효과는 잡균에 의한 오염 가능성을 제거시킬수 있었기 때문에 품질의 안정화를 위한 필수적인 공정으로 볼 수 있었다. 종초에서 분리된 산생성 균주의 생육과 산생성능을 조사한 결과, AH-1은 발효초기에 증식한 반면 AH-2는 발효 푸기에 증식하면서 산을 생성하였다. 따라서 이런 균주들이 서로 어우러져 최종적인 감식초의 품질을 결정하는 것으로 사료되었다. 감식초의 유기산 성분은 대부분이 acetic acid로 구성되어 있었고, 그 다음은 $\beta$-galac-turonic acid였다. 그리고 tanin 함량은 시판제품에 비하여 16~44mg% 정도 적게 나타났다.

• Korean Journal of Microbiology
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• v.27 no.2
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• pp.155-161
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• 1989

Lactobacillus sporogenes was treated with N-methyl-N'-nitro-N-nitrosoguanidine (NTG) to obtain resistant mutants to rifampicin. Fifty-eight strains of the NTG-induced mutants showed distinct resistance to rifampicin and nine mutants were selected for further studies. They also exhibited identical characteristics with the parent Lactobacillus sporogenes when they were tested for spore formation, acid formation and growth inhibition of E. coli. From in vitro test it was identified that rifampicin is not inactivated by certain factors of the rifampicin resistant mutants. It is suggested that they can be utilized as efficient normalizing agents for human intestinal flora when they are simultaneously taken with rifampicin

• Journal of the korean academy of Pediatric Dentistry
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• v.30 no.3
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• pp.439-447
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• 2003

This was performed to evaluate the inhibitory effect of laser on the growth of S. mutans. The bacterial pallets containing S. mutans KCTC 3065 were irradiated with Er:YAG laser and Nd :YAG laser by non-contact method at an intensity of 50mJ for 5 sec with the pulse repetition rates of 10Hz and 30Hz, respectively. The following results were obtained on colony count, acid producing ability, and the amount of insoluble extracellular polysaccharide synthesis. 1. The irradiation of Nd:YAG laser after photosensitization with Chinese ink inhibited the proliferation of S. mutans the most, and the irradiation of Er:YAG also inhibited the proliferation. However, the irradiation of Nd:YAG laser alone could not inhibited the proliferation of S. mutans. The pulse repetition rate did not affect significantly on the proliferation of bacteria in overall. 2. The irradiation of Nd:YAG laser after the photosensitization with Chinese ink inhibited the acid production of S. mutans the most for a certain period of time. Er:YAG laser also inhibited acid production. When Nd:YAG laser was used alone, the acid production of S. mutans was not been inhibited. The irradiation of Nd:YAG laser after photosensitization with Chinese ink inhibited the acid production ability of bacteria the most as the pulse repetition rate increased. 3. Laser irradiation did not inhibited the synthesis of insoluble extracellular polysaccharide of S. mutans. From these results, we conclude that the irradiation of Er:YAG laser and Nd:YAG laser after photosensitization with Chinese ink would inhibit the proliferation and acid production by S. mutans, which may prevent dental caries. However, this effect does not last long time so that the laser irradiation should be repeated frequently in order to obtain clinical effect; thus, this laser irradiation would not have a clinical usefulness in preventing dental caries when used solely.

• Journal of the korean academy of Pediatric Dentistry
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• v.41 no.3
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• pp.233-240
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• 2014

An in vitro study on cariogenic potential of four over-the-counter nutritional supplements for children was performed. The experimental groups were four over-the-counter nutritional supplements. The positive control group was 10% sucrose solution (S), and the negative control group was artificial saliva (T). The pH of each group, the buffering capacities, acid production, the microhardness changes of the bovine teeth specimens were measured. The pH of all experimental groups were lower than critical pH 5.5 where enamel demineralization starts. The buffering capacity of the Hama Vitamin Pharm (Hamsoa Pharm Co., Korea) was highest, and the Smart Chewable Vitamin A (JW Pharm Co., Korea) had the lowest buffering capacity. The reduction rates of the pH of the experimental groups were significantly higher than that of the negative control group (p < 0.05). The microhardness of enamel of all experimental groups and the positive control group significantly decreased. In contrast, the microhardness of enamel of the negative control group significantly increased after experiment (p < 0.05). The reduction rate of the microhardness of enamel of the Hama Vitamin Pharm (Hamsoa Pharm Co., Korea) was significantly higher and Hikid Plus (Sanga Pharm Co., Korea) was significantly lower than the other experimental groups.

• Korean journal of food and cookery science
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• v.4 no.2
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• pp.39-50
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• 1988

Main lactic acid bacteria fermenting “Baechu Kimchi” and” “Dongchim”, which are indigenous fermented food in Korea, were isolated at optimum fermentation period and identified. The three groups of food preservatives-sorbic acid, p-hydroxybutyl benzoate (POBB), p-hydroxypropyl benzoate (POPB), and sorbic acid-POBB were prepared, and the effect of the food preservatives and various salt concentrations on those lactic acid bacteria was examined. The results obatined are as follows; 1. Lactic acid bacteria were isolated from “Baechu Kimchi” and “Dongchimi”and identifed as Leuconostoc mesonteriodse, Lactobacillus plantatum, Lactobacillus brevis, Streptococcus faecalis, and Pedicoccus pentosaceus. 2. Lactic acid bacteria were grown much better at 0.5-2% NaCl level than 0% NaCl level. 3. Among the isolated lactic acid bactera, Lactobacillus plantarum showed the highest acid producibility. The lower the concentration of NaCl, the higher the acid producibility by Leuconostoc mesentroides, and the other bacteria produced a large amount of acid at 0.5-2.5% NaCl level. 4. Both the sorbic acid (0.05-0.1%) and sorbic (0.05%)-POBB (0.004%) groups showed the highest preservatives effect. In contrast, however, POPB (0.01% ) Group showed the lowest effect, and the preservatives effect was enhanced by the addition of NaCl. Lactobacillus plantarum was least affected by all preservatives, whereas Leuconostoc mesentroides was most affected by them.

• Microbiology and Biotechnology Letters
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• v.8 no.2
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• pp.87-92
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• 1980

These experiments were conducted to manage more safe the selected strains and improve their characteristics. The results obtained were as follows: Preservation on soil at the range of 0 to 5 C was suitable and there were no remarkable changes on their abilities to produce citric acid until 10 months preservation. The successive transfer of spore slightly stimulated the selected strain, M-315 to produce citric acid and the spore precultured on sporulation medium for 7-10 days was desirable as inoculum. Under UV-irradiation from the selected strains, 109 mutants whose morphological characteristics were changed were isolated. Among them, the mutant M-80-12 was shown 3.2％ increase on acid producing ability than that of its parent.

• Journal of the korean academy of Pediatric Dentistry
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• v.31 no.4
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• pp.605-616
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• 2004

Subinhibitory concentrations (sub-MICs) refer to concentrations below minimum inhibitory concentrations (MICs). The antimicrobial agents may be present at relatively high concentration, at least higher than bacterial MIC and thereafter be deserted off a surface and function at sub-MICs, perhaps by interfering with bacterial metabolism. Consequently, the aim of this study was to determine the effects of growth, in the presence of sub-MICs of antimicrobial agents, on the cell surface properties and virulence factors of mutans streptococci and to investigate the efficacy of a chemical approach in vitro. Streptococcus mutans Ingbritt and Streptococcus sobrinus 6715-7 were used. Eight antimicrobial agents (Sanguinaria extract;SG, Chlorhexidine digluconate;CHX, Fluoride;F, Propolis;PP, Hydrogen peroxide;HP, Triclosan;TC, Sodium dodecyl sulfate;SDS Cetylpyridinium chloride; CC) were diluted serially in broth to determine MICs and to compare the growth rate, acid production, hydrophobicity, adhesion activity to saliva coated hydroxyapatite, glucan synthesis and cellular aggregation of experiment groups (in the presence of sub-MICs) with those of control (in the absence of antimicrobial agents). Sub-MICs of antimicrobial agents affected the growth of cells, hydrophobicity, and adhesion of bacteria to saliva coated hydroxyapatite and glucan synthesis. They also resulted in a significant reduction in pH after 12 hours (p<0.05). By cells pretreated with proteinase K, either the aggregation induced by antimicrobial agents was completely inhibited or the aggregation titers were markedly increased. According to the results of the present study, each antimicrobial agent at sub-MICs could affect similar as its known action mechanism and could continually inhibit cariogenic bacteria at such concentrations. Thus, the use of these antimicrobial agents would be one of the effective methods to prevent dental caries.