Authors: Ashwag Shami, Amjad Alrebdi, Samiah Almijalli, Reema Almasri, Rasha Alsalem
Received 1 June 2023
Accepted for publication March 2024
Published June 2024 Volume 1:2 Pages 5—15
Checked for plagiarism Yes
Peer reviewer comments 2
Correspondence: shalmejale@pnu.edu.sa
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Abstract
The collective micro-community residing in the human body is called the microbiota. Studying and comparing its composition from different body sites is now a promising approach for microbiologists. The bacterial composition of the upper respiratory tract URT flora has been extensively studied, considering many factors, including health state, age, and gender. In our study, we identified the bacterial microbiota of two specific parts of the URT: mouth and nose. We isolated and identified bacteria from 40 males and 40 females using the VITEK biochemical identification method, followed by molecular identification using 16s rRNA primers. Fifteen bacterial genera were identified, making up 29 species, of which 11 were common in both genders. The two most identified genera are Staphylococcus, dominant in the nose but absent in the mouth, and Streptococcus, dominant in the mouth (p-value < 0.05). The Staphylococcus genus has a significantly higher “overall" number of culturable isolates (40% (p<0.05)), and the most abundant species of the Staphylococcus are S. epidermidis and S. aureus (41% and 39% of total Staphylococcus species). Age significantly affects the abundance and diversity of oral flora, with higher diversity in younger participants and higher abundance in the elderly, specifically oral Streptococcus (F=9.09, p-value= 0.003) young > old. Gender affects the abundance, where females have significantly higher oral bacterial density than males but no significant effect on the nasal system. Based on the unique microbial signatures retrieved from this study in each test group, elderly groups of both genders show more gram-negative pathogenic species than commensals, specifically the older females with a high abundance of Enterobacter cloacae complex
KEYWORDS: Microbiota, Oral and Nasal Cavities, Biochemical, Molecular, Bacteria
