The purpose of this study was to prevent cross-contamination of dental hygienists by aerosols. We performed prophylactic scaling on 30 patients who visited the dental clinic. Microbiologic identification and SEM imaging were performed to confirm the number of microorganisms in the aerosol. Data analysis showed significant difference between two groups using SPSS (ver.21). According to the results, it was confirmed that Gram-positive and Gram-negative microorganisms were present in the aerosol, and these microorganisms were identified as microbes causing opportunistic infection in human body. In addition, chlorhexidine gargles were reduced to a significant level to reduce the number of microorganisms in the aerosol. A dental hygienist is likely to stay in a clinic room for a long time and be exposed to the generated aerosols. In order to prevent this, dental hygienists must thoroughly implement protection through personal protective equipment such as face shields and mask. In addition, reducing the number of microorganisms in the patient's mouth can be used gargling agents. In conclusion, the risks of cross-infection will be reduced through these methods.

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Consumers are increasingly concerned about the origin of foods, so the geographical origin of foods has been a major topic of debate and extensive research. Various instrumental methods (e.g. high performance liquid chromatography (HPLC), gas chromatography (GC), capillary electrophoresis (CE), electronic nose, near-infrared spectroscopy (NIRS), nuclear magnetic resonance spectroscopy (NMR), DNA analysis, multi-isotope analysis) in conjunction with statistical analysis, were developed and applied in attempt to provide reliable answers to their geographical origin. This study reviews current developments in the application of various methods for a clear geographical origin of foods. The limitation of discrimination analysis for geographical origin was also discussed.

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l-Carnitine is an essential compound that shuttles long chain fatty acids into mitochondria. The objective of this study was to produce l-carnitine enriched oyster mushroom (Pleurotus ostreatus) using common buckwheat fermented by Rhizopus oligosporus. Mushroom grown on common buckwheat medium contained 9.9–23.9% higher l-carnitine (186.3 mg/kg) than those grown on basal medium without any buckwheat addition. Those grown on fermented common buckwheat medium contained the highest l-carnitine content (201.2 mg/kg). Size index and lightness of mushroom pileus (L*) were also the highest (100.7 and 50.6, respectively) for those grown in medium added with fermented common buckwheat (20%, w/w). Antioxidant activities of both mushroom extracts (1.5 mg/mL) showed the same level as 38.7% for mushroom grown in media added with common buckwheat or fermented common buckwheat. At the treatment concentration of 300 μg/mL, viabilities of murine macrophage cell line Raw 264.7 cells treated with ethanol extract of oyster mushroom grown on buckwheat medium ranged from 58.9 to 67.8%. The oyster mushroom grown on buckwheat and fermented buckwheat medium can be used as one of the substitutes for meat based diets.Electronic supplementary materialThe online version of this article (10.1186/s13568-018-0664-6) contains supplementary material, which is available to authorized users.

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Objectives : The aim of this study is to evaluate the surface changes of enamel specimen, tooth structure by toothpastes in child and adult.Methods : Experimental teeth were collected from extracted human primary teeth. 120 enamel specimens were prepared by cutting the teeth into 2×3×2 mm blocks using diamond saw and the specimens were assigned to 3 groups. Group 1 was used as control with no treatment. Group 2 was treated with child toothpaste and Group 3 was treated with adult toothpaste on primary enamel surface for 3 minutes daily over 4 weeks. The specimens were immersed into individual container having artificial saliva and the artificial saliva was changed every day. The electron probe micro analyzer(EPMA) provided weight percent(wt%) of calcium(Ca) and phosphorous(P) on enamel surface. The morphology was analyzed by scanning electron microscopy(SEM). Data were analyzed by one-way analysis of variance(ANOVA) and Tukey's test post-hoc test using SPSS(Version 20, SPSS Inc., Chicago, USA). Level of significance was set at 0.05.