Distinguishable Shot-term Effects of Tea and Water Drinking on Human Saliva Redox

Abstract

Food consumption can alter the biochemistry and redox status of human saliva, and the serving temperature of food may also play a role. The study aimed to explore the immediate (3 min) and delayed (30 min) effects of hot tea (57±0.5℃) ingestion and cold tea (8±0.5℃) ingestion on the salivary flow rate and salivary redox-relevant attributes. The saliva was collected from 20 healthy adults before, 3-min after and 30-min after the tea ingestion. The hot or cold deionised water at the same temperatures were used as control. The salivary flow rate and redox markers in hot tea (HBT), cold tea (CBT), hot water (HW) and cold water (CW) group wereanalysedand compared. The results demonstrated that neither the black tea nor the water altered the salivary flow rate; the black tea immediately increased the salivary thiol (SH) and malondialdehyde (MDA) content while reduced salivary uric acid (UA) significantly. The tea ingestion showed a tendency to elevate the ferric reducing antioxidant power (FRAP) in saliva, although not significantly. The water ingestion decreased the MDA content immediately and increased the UA level significantly. Cold water was found to induce a greater delayed increase in total salivary total protein (TPC) than the hot water. In conclusion, the black tea ingestion affects the redox attributes of human saliva acutely and significantly, while the temperature of drink makes the secondary contribution.

Incidental nanoparticles in black tea alleviate DSS-induced ulcerative colitis in BALB/c mice

“…23 The in vitro cellprotective activities of black tea nanoparticles, together with the co-existence of polyphenols and polysaccharides in the particles, show good potential in regulating intestinal barrier function and mucosal immunity in vivo. We have shown that the ingestion of black tea infusion immediately increased the salivary thiol (SH) and malondialdehyde (MDA) contents while reducing salivary uric acid (UA), 24 demonstrating the direct influences of tea infusion on oral mucosal cells. The black tea NPs aggregate under the acidic pH conditions of the stomach to form agglomerates and become more resistance to gastric digestion.…”