Components in Lentinus edodes mushroom with anti-biofilm activity directed against bacteria involved in caries and gingivitis.

The present study investigated the compounds present in the low molecular mass fraction of Lentinus edodes mushroom (shiitake) extract and their anti-virulence activity against oral pathogens (reference and clinical Streptococcus mutans, Actinomyces naeslundii, and Prevotella intermedia strains). Oxalic, succinic, and quinic acids, and adenine, inosine, and uridine were identified by HPLC-DAD-ESI-MS/MS. Their anti-biofilm production and preformed biofilm disaggregation activities were studied using commercial standard compounds at different concentrations. As regards S. mutans, the highest activity was shown by adenine at 5 mg mL-1 both in the biofilm inhibition (BI 50%) and biofilm disaggregation tests (BD 20%). Considering A. naeslundii, BI values close to 80% were registered for oxalic acid at 1 mg mL-1 and 2 mg mL-1 and BD 50% for quinic acid at 3 mg mL-1. A weaker activity was found against P. intermedia. Furthermore, different mixtures of the commercial standards were tested showing that the activity of a compound can be strongly and sometimes negatively affected by the presence of the other compounds.

Comparison of Carisolv system vs traditional rotating instruments for caries removal in the primary dentition: A systematic review and meta-analysis.

OBJECTIVE: The purpose of this systematic review and meta-analysis was to evaluate the reliability of the Carisolv system with respect to drilling regarding the full removal of decayed hard tissues in primary dentition. A systematic review of the literature was conducted to identify controlled trails, randomized controlled trials and clinical trials that compared the Carisolv system to the traditional mechanical caries removal in the primary dentition. MATERIALS AND METHODS: The main relevant databases were searched: MEDLINE via PUBMED, Web of Science and SCOPUS. Complete caries removal, length of working time and need of local anesthesia were the outcomes evaluated. RESULTS: A total of 195 studies were identified and complete analysis of 28 studies was performed; finally, 10 papers were included. The trials included involved a total of 348 patients for 532 treated teeth. There was no significant difference in terms of clinical efficacy between the Carisolv and the rotary instrument (z = 0.68, p = 0.50), whereas the treatment with Carisolv was significantly longer in terms of time with respect to the rotary instruments (z = 10.49, p < 0.01). The chemo mechanical technique reduces the need for local anesthesia, with a difference between two types of treatment near to statistical significance (z = 1.91 p = 0.06). CONCLUSIONS: This systematic review indicates that the clinical efficacy of chemo-mechanical removal with Carisolv seems as reliable as the rotary instruments. However, the results should be interpreted cautiously due to the heterogeneity among study designs and to the shortage of available data. Further large-scale, well-designed randomized controlled trials are needed.

The anti-adhesive mode of action of a purified mushroom (Lentinus edodes) extract with anticaries and antigingivitis properties in two oral bacterial phatogens.

BACKGROUND: In previous works we have shown that a low-molecular-mass (LMM) fraction from mushroom (Lentinus edodes) homogenate interferes with binding of Streptococcus mutans to hydroxyapatite and Prevotella intermedia to gingival cells. Additionally, inhibition of biofilm formation of both odonto- and periodonto-pathogenic bacteria and detachment from preformed biofilms have been described for this compound. Further purification of mushroom extract has been recently achieved and a sub-fraction (i.e. # 5) has been identified as containing the majority of the mentioned biological activities. The aim of this study was to characterise the bacterial receptors for the purified mushroom sub-fraction #5 in order to better elucidate the mode of action of this compound when interfering with bacterial adhesion to host surfaces or with bacteria-bacteria interactions in the biofilm state. METHODS: Candidate bacterial molecules to act as target of this compound were bacterial surface molecules involved in cell adhesion and biofilm formation, and, thus, we have considered cell wall associated proteins (CWPs), teichoic acid (TA) and lipoteichoic acid (LTA) of S. mutans, and outer membrane proteins (OMPs) and lipopolysaccharide (LPS) of P. intermedia. RESULTS: Fifteen S. mutans CWPs and TA were capable of binding sub-fraction #5, while LTA did not. As far as P. intermedia is concerned, we show that five OMPs interact with sub-fraction # 5. Capacity of binding to P. intermedia LPS was also studied but in this case negative results were obtained. CONCLUSIONS: Binding sub-fraction # 5 to surface molecules of S. mutans or P. intermedia may result in inactivation of their physiological functions. As a whole, these results indicate, at molecular level, the bacterial surface alterations affecting adhesion and biofim formation. For these antimicrobial properties, the compound may find use in daily oral hygiene.

Fluoride content in breast milk after the use of fluoridated food supplement. A randomized clinical trial.

PURPOSE: To evaluate if the intake of a fluoridated food supplement in breastfeeding mothers increases the fluoride concentration in breast milk. METHODS: A double-blind randomized placebo-controlled study was designed. Two groups of women were formed: a fluoride group (n = 112), using a non-sucrose food supplement containing fluoride (1,500 µg/l for each dose) and a control group (n = 116), using a non-sucrose food supplement without fluoride content. The women were followed for 6 weeks. Samples of breast milk were collected and analyzed using an ion-specific electrode. RESULTS: 85 women in the fluoride group and 83 in the control group concluded the trial. Fluoride concentrations in the two groups were statistically significantly different (515 µg/l in the fluoride and 476 µg/l in the control group P= 0.04) at the end of the experimental period. In the fluoride group, a statistically significant increment in fluoride concentration during the experimental period was also observed (from 468 ± 104 µg/l to 515 ± 105 µg/l). The use of a non-sucrose food supplement containing fluoride resulted in a significant increment in fluoride concentration in breast milk.

Effects of mushroom and chicory extracts on the shape, physiology and proteome of the cariogenic bacterium Streptococcus mutans.

BACKGROUND: Dental caries is an infectious disease which results from the acidic demineralisation of the tooth enamel and dentine as a consequence of the dental plaque (a microbial biofilm) accumulation. Research showed that several foods contain some components with antibacterial and antiplaque activity. Previous studies indicated antimicrobial and antiplaque activities in a low-molecular-mass (LMM) fraction of extracts from either an edible mushroom (Lentinus edodes) or from Italian red chicory (Cichorium intybus). METHODS: We have evaluated the antimicrobial mode of action of these fractions on Streptococcus mutans, the etiological agent of human dental caries. The effects on shape, macromolecular syntheses and cell proteome were analysed. RESULTS: The best antimicrobial activity has been displayed by the LMM mushroom extract with a bacteriostatic effect. At the MIC of both extracts DNA synthesis was the main macromolecular synthesis inhibited, RNA synthesis was less inhibited than that of DNA and protein synthesis was inhibited only by roughly 50%. The partial inhibition of protein synthesis is compatible with the observed significant increase in cell mass. The increase in these parameters is linked to the morphological alteration with transition from cocci of the untreated control to elongated cells. Interestingly, these modifications were also observed at sub-MIC concentrations. Finally, membrane and cytosol proteome analysis was conducted under LMM mushroom extract treatment in comparison with untreated S. mutans cells. Significant changes were observed for 31 membrane proteins and 20 of the cytosol fractions. The possible role of the changed proteins is discussed. CONCLUSIONS: This report has shown an antibiotic-like mode of action of mushroom and chicory extracts as demonstrated by induced morphogenetic effects and inhibition of specific macromolecular synthesis. This feature as well as the safe use of this extract as result of its natural origin render the LMM both mushroom and chicory extracts suitable for the formulation into products for daily oral hygiene such as mouthwashes or toothpastes.

Adhesive microbeads for the targeting delivery of anticaries agents of vegetable origin.

The formulation of quinic acid, a food constituent demonstrating potential anticaries and antigingivitis properties, was investigated in an adhesive microparticulate delivery system with the goal of improving its effect by prolonging its residence time at the site of action. Alginate and chitosan were selected as mucoadhesive polymers. The microspheres were prepared by coacervation. Different types of alginates, polymers blends and crosslinking agent concentrations were considered and evaluated. The best results in terms of encapsulation efficiency, in vitro active agent release profile and in vitro adhesive properties, both to oral mucosa and to teeth surface, were obtained with a blend of Alginate Protanal LF200S: Alginate Protanal LF120LS 1:1.5 w/w, 0.1M CaCl(2), and chitosan coating, prepared by a one-step complex coacervation method. This microparticulate delivery system showed prolonged release of quinic acid, and could be used as an active component in chewing gums or mouthwashes for both caries and gingivitis prevention.

Identification of organic acids in Cichorium intybus inhibiting virulence-related properties of oral pathogenic bacteria.

The low molecular mass (LMM) extract of Cichorium intybus var. silvestre (red chicory) has been shown to inhibit virulence-linked properties of oral pathogens including Streptococcus mutans, Actinomyces naeslundii and Prevotella intermedia. In the present study HPLC-DAD-ESI/MS(2) was used to investigate the compounds contained in this extract for their anti-virulence activity. The extract contained a number of components, including oxalic, succinic, shikimic and quinic acids, which interfere with the growth and virulence traits (i.e., biofilm formation, adherence to epithelial cells and hydroxyapatite) of oral pathogens involved in gingivitis and tooth decay. Succinic and quinic acid seem to be the most potent, mainly by interfering with the ability of oral pathogens to form biofilms (either through inhibition of their development or promotion of their disruption). Our findings suggest that one or more of these compounds may modulate plaque formation in vivo, which is a prerequisite for the development of both caries and gingivitis.

The short-term treatment effects on the microbiota at the dorsum of the tongue in intra-oral halitosis patients--a randomized clinical trial.

OBJECTIVES: This study aims to assess the effects of rinsing with zinc- and chlorhexidine-containing mouth rinse with or without adjunct tongue scraping on volatile sulfur compounds (VSCs) in breath air, and the microbiota at the dorsum of the tongue. MATERIAL AND METHODS: A randomized single-masked controlled clinical trial with a cross-over study design over 14 days including 21 subjects was performed. Bacterial samples from the dorsum of the tongue were assayed by checkerboard DNA-DNA hybridization. RESULTS: No halitosis (identified by VSC assessments) at day 14 was identified in 12/21 subjects with active rinse alone, in 10/21 with adjunct use of tongue scraper, in 1/21 for negative control rinse alone, and in 3/21 in the control and tongue scraping sequence. At day 14, significantly lower counts were identified only in the active rinse sequence (p < 0.001) for 15/78 species including, Fusobacterium sp., Porphyromonas gingivalis, Pseudomonas aeruginosa, Staphylococcus aureus, and Tannerella forsythia. A decrease in bacteria from baseline to day 14 was found in successfully treated subjects for 9/74 species including: P. gingivalis, Prevotella melaninogenica, S. aureus, and Treponema denticola. Baseline VSC scores were correlated with several bacterial species. The use of a tongue scraper combined with active rinse did not change the levels of VSC compared to rinsing alone. CONCLUSIONS: VSC scores were not associated with bacterial counts in samples taken from the dorsum of the tongue. The active rinse alone containing zinc and chlorhexidine had effects on intra-oral halitosis and reduced bacterial counts of species associated with malodor. Tongue scraping provided no beneficial effects on the microbiota studied. CLINICAL RELEVANCE: Periodontally healthy subjects with intra-oral halitosis benefit from daily rinsing with zinc- and chlorhexidine-containing mouth rinse.

Plant and fungal food components with potential activity on the development of microbial oral diseases.

This paper reports the content in macronutrients, free sugars, polyphenols, and inorganic ions, known to exert any positive or negative action on microbial oral disease such as caries and gingivitis, of seven food/beverages (red chicory, mushroom, raspberry, green and black tea, cranberry juice, dark beer). Tea leaves resulted the richest material in all the detected ions, anyway tea beverages resulted the richest just in fluoride. The highest content in zinc was in chicory, raspberry and mushroom. Raspberry is the richest food in strontium and boron, beer in selenium, raspberry and mushroom in copper. Beer, cranberry juice and, especially green and black tea are very rich in polyphenols, confirming these beverages as important sources of such healthy substances. The fractionation, carried out on the basis of the molecular mass (MM), of the water soluble components occurring in raspberry, chicory, and mushroom extracts (which in microbiological assays revealed the highest potential action against oral pathogens), showed that both the high and low MM fractions are active, with the low MM fractions displaying the highest potential action for all the fractionated extracts. Our findings show that more compounds that can play a different active role occur in these foods.

Effects of mushroom and chicory extracts on the physiology and shape of Prevotella intermedia, a periodontopathogenic bacterium.

Contrary to the common assumption that food has a negative impact on oral health, research has shown that several foods contain a number of components with antibacterial and antiplaque activity. These natural compounds may be useful for improving daily oral hygiene. In this study we evaluate the mode of antimicrobial action of fractions of mushroom and red chicory extracts on Prevotella intermedia, a periodontopathogenic bacterium. The minimal inhibitory concentration corresponded to 0.5x compared to the natural food concentration for both extracts. This concentration resulted in a bacteriostatic effect in mushroom extract and in a slightly bactericidal effect in chicory extract. Cell mass continued to increase even after division stopped. As regards macromolecular synthesis, DNA was almost totally inhibited upon addition of either mushroom or chicory extract, and RNA to a lesser extent, while protein synthesis continued. Cell elongation occurred after septum inhibition as documented by scanning electron microscopy and cell measurement. The morphogenetic effects are reminiscent of the mode of action of antibiotics such as quinolones or ß-lactams. The discovery of an antibiotic-like mode of action suggests that these extracts can be advantageously employed for daily oral hygiene in formulations of cosmetic products such as mouthwashes and toothpastes.

Effects of fruit and vegetable low molecular mass fractions on gene expression in gingival cells challenged with Prevotella intermedia and Actinomyces naeslundii.

Low molecular mass (LMM) fractions obtained from extracts of raspberry, red chicory, and Shiitake mushrooms have been shown to be an useful source of specific antibacterial, antiadhesion/coaggregation, and antibiofilm agent(s) that might be used for protection towards caries and gingivitis. In this paper, the effects of such LMM fractions on human gingival KB cells exposed to the periodontal pathogens Prevotella intermedia and Actinomyces naeslundii were evaluated. Expression of cytokeratin 18 (CK18) and ß4 integrin (ß4INT) genes, that are involved in cell proliferation/differentiation and adhesion, and of the antimicrobial peptide ß2 defensin (HßD2) in KB cells was increased upon exposure to either live or heat-killed bacteria. All LMM fractions tested prevented or reduced the induction of gene expression by P. intermedia and A. naeslundii depending on the experimental conditions. Overall, the results suggested that LMM fractions could modulate the effects of bacteria associated with periodontal disease in gingival cells.

Effects of mouthrinses containing essential oils and alcohol-free chlorhexidine on human plaque acidogenicity.

The aim of this in vivo study was to evaluate the effect of two antimicrobial mouthrinses on dental plaque acidogenicity after a sucrose challenge. Twenty subjects, with a mean age of 59 years, participated in a double-blind intraindividual randomized study. Three mouthrinses were used in 16-day rinsing periods in addition to their regular mechanical oral hygiene: a solution with essential oils (EO), solution with alcohol-free chlorhexidine (CHX) and water (negative control). The three test periods were separated by 3-month washout periods. Changes in plaque acidogenicity were evaluated after a sucrose challenge at day 0 (baseline) and at day 17 of each mouthrinse period using the microtouch method. Both CHX and EO resulted at day 17 in statistically significant less attenuated pH falls compared to the water rinse. The CHX mouthrinse resulted in the least pronounced pH values compared with EO (ns) during the whole 30-min period. When calculated as area under the curve (AUC), significantly lower values (AUC(6.2) ) were found for CHX and EO at day 17 compared to day 0. A significant difference for AUC(6.2) between CHX and water was found at day 17. No statistically significant differences were found for any of the comparisons with AUC(5.7). The results from this study indicate that both the essential oils and the alcohol-free chlorhexidine reduced plaque acidogenicity after a sucrose challenge. Large interindividual variations were observed.

Strong antibacterial effect of miswak against oral microorganisms associated with periodontitis and caries.

BACKGROUND: The chewing stick (miswak) is used for oral hygiene in many parts of the world. In addition to the mechanical removal of plaque, an antibacterial effect has been postulated; however, tests of miswak extract from Salvadora persica (Arak) disclosed only low to moderate antibacterial effects. This may be attributable to the extraction process. Our aim was to test in vitro the antibacterial effect of miswak pieces, without extraction, on bacteria implicated in the etiology of periodontitis and caries. METHODS: Miswak pieces were standardized by size and weight (0.07 and 0.14 g) and tested against Streptococcus mutans, Lactobacillus acidophilus, Aggregatibacter actinomycetemcomitans (previously Actinobacillus actinomycetemcomitans), Porphyromonas gingivalis, and, as a reference, Haemophilus influenzae. The miswak pieces were tested in two ways: embedded in the agar plate or suspended above the agar plate. RESULTS: The inhibitory effect was most pronounced on P. gingivalis, A. actinomycetemcomitans, and H. influenzae, less on S. mutans, and least on L. acidophilus. Suspended miswak had comparable or stronger effects than miswak embedded in agar. The 0.14-g suspended miswak exhibited significantly greater inhibition on A. actinomycetemcomitans and H. influenzae than the 0.14-g miswak embedded in agar (P<0.01 and P<0.001, respectively). CONCLUSIONS: Miswak embedded in agar or suspended above the agar plate had strong antibacterial effects against all bacteria tested. The antibacterial effect of suspended miswak pieces suggests the presence of volatile active antibacterial compounds.