Retention of ingested phospholipids on the oral mucosa

Bananas contain surface active phospholipids (PL) and may potentially be a cheap and palatable means of administering exogenous PL to the pharyngeal mucosa for the treatment of obstructive sleep apnoea. Method: Eight healthy women (20.1 ± 1.4 years of age) were studied to determine how long banana PL are retained on oral epithelial surfaces. Epithelial cells were gently scraped from the inside of the subjects' cheeks immediately before, and 1, 2, 4 and 6 hours after, subjects slowly drank 200 ml of an aqueous suspension containing 130 grams of ripe Cavendish banana. Fifty epithelial cells per cheek scraping sample were examined with epi-fluorescent microscopy after staining with the lipophilic fluorescent dye Nile red. Results: Cells collected before banana ingestion (BI) showed no evidence of epi-fluorescence, but the large majority of cells after BI displayed red epi-fluorescence indicative of PL. The diagram (mean data from 8 subjects) shows that the intensity of epi-fluorescence, was largely retained 6 hours after BI. Conclusion: Retention of ingested PL on epithelial surfaces may enable PL to exert a pharyngeal patency promoting action throughout an entire night which may prove to be of value in the treatment of obstructive sleep apnoea.