The effect of mouthwash on the DNA yield and quality of oral bacteria

Aims@#The application of mouthwash is one of the oral hygiene treatments that commonly use after tooth brushing to control the bacterial colonization from overgrowth. This research is focused on investigating the effect of mouthwash on oral microbiome by analyzing the quality and yield of DNA obtained before and after using mouthwash and also to compare the bacterial abundance via 16S rRNA PCR detection.@*Methodology and results@#The DNA was extracted from the saliva samples before and after using mouthwash using Phenol-Chloroform extraction method. The DNA extract was then evaluated using Nano Drop ND-1000 UV/VIS Spectrophotometer to determine the DNA quality and DNA yield. After that, the 16S rRNA gene was amplified via PCR for bacterial detection in the saliva using 27 F and 1492 R primers set, and the PCR products were observed on 1.5% gel electrophoresis. Statistical analysis was performed by using Graphpad Prism 7.03 software. For DNA yield, there was significantly higher yield observed after mouthwash usage with 80% of the samples was found to yield more DNA. To assess DNA quality, absorbance ratio of A260/A280 and A260/A230 were used. The DNA quality was seen to be similar for both A260/A280 and A260/A230 absorbance ratio even after the usage of mouthwash. The amplification of 16S rRNA gene was successful and 1500 bp expected band size was observed.@*Conclusion, significance and impact of study@#This study demonstrated the usage of mouthwash is useful to increase the DNA yield as compared to without using mouthwash. However in terms of quality, no difference is seen. This result can be used to provide insight on mouthwash usage for saliva sampling in a non-invasive manner.

Effect of preservatives, temperature and storage duration on stability of nucleic acids of pleopod tissues of Penaeus vannamei (Boone) and screening of viral infections.

In shrimp farming, screening for economically significant viral pathogens in nucleic acids of shrimps is vital for disease surveillance programmes and further, to take necessary precautions to ensure the sustainability of the farms and thereby the shrimp industry. Different preservatives, temperature and storage durations of the pleopod tissues of Penaeus vannamei broodstock were tested to investigate its effect on the quality and quantity of the nucleic acids. The pleopods were subjected to two preservation regimes and the yield and stability of the extracted nucleic acids were monitored over a time period of 12 months. Stability of the nucleic acids was assessed with nested polymerase chain reaction, and the yield was checked spectrophotometrically. Data was analysed by performing two way ANOVA and Tukeys Paired test. Preservation treatments included storage at −20°C and 5°C in RNAlaterTM and in 70 % ethanol. Significant variation (P<0.05) was observed in both DNA and RNA yield and stability from ethanol and RNAlaterTM stored pleopods at 5°C. However, the yield and stability did not differ (P >0.05) in both the preservatives at −20°C. The RNA was degraded and yielded lesser quantity when pleopod tissues were stored in ethanol at −20°C than when stored in RNAlaterTM during storage duration of 9 months. This study would help the shrimp farmers and researchers to adopt better preservation strategy, vital for shrimp disease surveillance programmes and for traceability studies in the event of any disease outbreak.