Impact of Refined and Unrefined Sugar and Starch on the Microbiota in Dental Biofilm.

Aims and Objective: Sugar is not only associated with dental diseases but also, along with carbohydrates, is linked to various health issues including obesity, cancer, diabetes, heart, liver, and kidney-related diseases. At the same time, a polyphenol present in unrefined sugar and starch (UReSS) is shown to inhibit microbial growth and prevent biofilms and dental plaque. The question arises, "is sugar the causative agent for dental diseases, or is its refined form the cause?" The objective of this study is to conduct in-vivo studies of the impact of refined and unrefined sugar and starch on the microbiota of dental biofilm. Materials and Methods: An in-vivo study was performed using saliva and dental biofilm samples collected from 75 healthy subjects. For this study, healthy volunteers (n = 75) were randomly divided into five groups and were given sweet meals either made with refined white sugar and white rice (ReSS) or with unrefined brown sugar and red rice (UReSS). This was followed by using or not using a polyphenolic mouthwash. Before and after 4 h of eating a sweet meal, the saliva and dental plaque were collected and the DNA was analyzed by 16s metagenomic sequencing. The results were expressed in fold change of bacteria from 0 to 4 h. Statistical analyses have been performed by logarithmic linear discriminant analysis (LDA), Student's t-test, and Wilcoxon signed-rank test. Results: Upon LEfSe and statistical analysis, in-vivo experiments clearly showed that UReSS significantly decreased bacteria associated with dental diseases. In contrast, ReSS showed a significant increase in Actinomyces, Streptococcus, and Selenomonas with a high LDA score (Log 4.2) and statistical significance (P < 0.003). Mouthwash significantly decreased bacterial taxa associated with diseases in both the ReSS and UReSS groups. The in-vivo study showed a significant increase and decrease in Streptococcus levels in refined and unrefined sugar groups, respectively. Conclusion: In conclusion, polyphenols aid in the prevention of dental caries. This study recommends using polyphenol-rich unrefined sugars and carbohydrates for both oral and general health. This study is the first of its kind to bring awareness to the effects of refined and unrefined starch and sugars on the oral microbiota.

A Novel, Simple, Frequent Oral Cleaning Method Reduces Damaging Bacteria in the Dental Microbiota.

AIM: Dental diseases can be prevented by reducing early bacterial colonization in biofilm, a precursor to mature dental plaque. Most studies on dental disease pathogenesis focus on mature plaque and fail to address the impact of oral cleaning on biofilm formation. Here we used next-generation metagenomics to assess the effects of a new method of regular, simple biofilm disruption on the oral metagenome. MATERIALS AND METHODS: This was a randomized, controlled study of 45 healthy children divided into three groups. Participants avoided oral cleaning for 3 days and then performed 10 days of oral cleaning either by: (1) brushing and tongue cleaning twice a day (BT) with toothpaste; (2) Gum and tooth rubbing with Index Finger Tongue cleaning and water Swishing (GIFTS) after each meal, snack, and drink; or (3) GIFTS twice a day with nano-charcoal and tongue cleaning (CT) (n = 15 per group). Saliva, plaque, and tongue scraping samples were collected on day 0 and 10 for quantitative polymerase chain reaction (qPCR) and next-generation metagenomics sequencing to analyze microbiome taxa differences between groups. RESULTS: GIFTS more significantly reduced (P < 0.004) total bacteria in saliva than BT (P < 0.02). Metagenomics revealed a significant reduction in Firmicutes in GIFTS and CT tongue samples compared to BT samples. BT and CT saliva samples showed significantly more Streptococcus species than GIFTS saliva samples. In the plaque samples, GIFTS cleaning significantly reduced early colonizers, including Streptococcus, compared to the BT and CT methods. CONCLUSION: Here, we introduce the "frequent disruption of biofilm" concept for enhanced oral hygiene. GIFTS can be used to prevent early bacterial colonization of biofilm and plaque formation in both small children and adults. Frequent biofilm disturbance more effectively disrupts early bacterial colonization than twice oral cleaning, is nonabrasive, and is, therefore, a practical and straightforward complement to regular toothbrushing for improved oral hygiene and disease prevention.

Real-time and conventional PCR detection of Liberty Link rice varieties and transgenic soy in rice sampled in the Mexican and American retail markets.

Samples of rice from Mexican and USA retail stores were analyzed for the presence of transgenic (GM) events using real-time PCR. In screening for the CaMV35S promoter sequence (35SP), positive results were found in 49 and 35% of the Mexican and American samples, respectively. In further investigations in Mexican samples, 43% were positive for P35S::bar, with two above the quantifiable limit; these were 0.07% and 0.05% GMO. Fourteen out of the sixteen positive samples were labeled as imported from the USA. In testing samples bought in American retail shops, 24% showed positive results, all below the quantifiable range. It could be deduced that P35S::bar positive samples were Liberty Link(R) (LL) rice. In distinguishing between LL601 and LL62, end-point PCR was used, corroborating the P35S::bar amplicon length difference of these events. LL62 was found in one rice sample purchased in Mexico and two in the USA samples. Its presence was verified with the 35S terminator sequence. All other LL positive samples contained LL601. None of the samples analyzed showed the presence of Bt63 rice. The LL rice varieties found have been identified as not being commercially cultivated, and so their presence requires further investigation. 35SP was also present in samples which did not have any LL rice. Maize sequences could not be detected in any of the samples; however, soybean DNA was found in Mexican and USA rice samples. The Roundup Ready(R) trait was detected in trace amounts in 16 and 6% of the rice samples bought in Mexico and the USA, respectively. Real-time PCR was shown to be the method of choice for the sensitive and rapid screening of commodities and retail samples for the detection of GM and other contamination.

Suitability of real-time quantitative polymerase chain reaction and enzyme-linked immunosorbent assay for cry9C detection in Mexican corn tortillas: fate of DNA and protein after alkaline cooking.

Alkaline-cooked corn, called nixtamal, is the basis for many traditional corn products such as tortillas, chips, and taco shells that are used widely in Mexico and Central America and in the preparation of snack foods that are consumed globally. To assess the effects of alkaline and thermal treatments on the detectability of DNA and protein for the presence of genetically modified sequences, various nixtamalized products were prepared from blends of conventional white corn containing 0.1, 1.0, and 10% transgenic corn (event CBH 351, StarLink). Real-time quantitative polymerase chain reactions (RTQ-PCR) and immunoassays were used to determine the cry9C gene and protein, respectively, in unprocessed corn kernels, freshly prepared alkaline-cooked and ground corn (masa), masa flour, tortillas prepared from masa by heat treatment, chips prepared from damp masa dough by deep frying, and from tortillas processed at high (200 degrees C) and low temperatures (70 degrees C). In spite of progressive degradation of genomic DNA during processing, RTQ-PCR genetic analysis allowed detection and quantification of the cry9C gene in all products prepared from 10, 1, and 0.1% StarLink corn, except deep-fried chips containing 0.1% StarLink. Enzyme-linked immunosorbent assays readily detected <1 ppm cry9C protein in all blends of unprocessed corn (10, 1, and 0.1% StarLink) as well as in nonfried tortilla and masa products. This technique was not suitable for thermally treated nixtamalized products containing <1% transgenic corn.