Anti-Acetylcholinesterase Activity of Commercially Important Ceylon Black Tea (Camellia sinensis L.) Grades Belonging to Different Elevations: Potential Natural Product for Type 3 Diabetes Management?

Aims: Sri Lankan tea which is known as the Ceylon tea is the world’s finest tea. Currently Sri Lanka remains as the second main black tea (BT) exporter and the main orthodox BT exporter in the world. Although several pharmacological activities of Ceylon tea have been reported, its anti-acetylcholinesterase (AChE) activity which has a direct relationship with the management of Alzheimer's disease or type 3 diabetes has not reported to date. Further, there are no comprehensive studies on anti-AChE activity of tea world over. Present study evaluated anti-AChE activity of commercially important Ceylon BT grades belonging to different elevations. Methodology: Freeze dried hot water extracts of Broken Orange Pekoe Fannings (BOPF), Orange Pekoe (OP) and Dust No.1 BT grades from low, mid and high grown elevations and a Ceylon green tea sample collected from the local market were studied for anti-AChE activity using 96 well micro plate-based assay (n=3 each). Results: Results showed that all tested Ceylon tea had anti-AChE activity with varying degrees of potentials in a dose dependent manner. The mean IC50 values of BOPF, OP and Dust No. 1 tea grades at different elevations varied from 499.61±10.95 - 569.19±5.78, 598.80±24.95 - 677.81±6.61 and 509.44±3.81 - 621.39±3.29 µg/mL respectively. Interestingly, observed anti-AChE activity of black tea showed significant differences (P< 0.05) among elevations. The order of potency of BOPF, OP and Dust No:1 BT for anti-AChE activity at different elevations was low grown>high grown=mid grown, high grown=low grown>mid grown and mid grown>low grown>high grown respectively. Anti-AChE activity of Ceylon green (433.96 ± 5.95 µg/mL) tea was significantly high (P<0.05) compared to the tested BT and activities of all Ceylon tea were moderate compared to the reference standard Galantamine (IC50:2.52±0.17 µg/mL). Conclusion: It is concluded that selected Ceylon BT grades had varying levels of anti-AChE activity and it varied with the elevations

In vitro anti-hyaluronidase activity of Sri Lankan low grown orthodox orange pekoe grade black tea (Camellia sinensis L.)

Objective: To access the anti-hyaluronidase activity of Sri Lankan low grown orthodox orange pekoe (OP) grade black tea with a view to develop an anti-aging skin formulation. Methods: Five concentrations (0.125, 0.250, 0.500, 1.000 and 2.000 mg/mL) of black tea brew (BTB) were made using a freeze dried sample of Sri Lankan low grown orthodox OP grade black tea which was prepared according to international organization for standardization specification. Epigallocatechin gallate (EGCG) was used as the reference agent (concentrations tested: 0.012, 0.025, 0.050, 0.100 and 0.200 mg/mL). Anti-hyaluronidase activity of BTB and EGCG in vitro were ascertained spectrometrically using hyaluronic acid (from rooster comb) and bovine testicular hyaluronidase. Results: The results revealed that BTB had moderate [IC50=(1.09±0.12) mg/mL] and dose dependent (r2=0.94) anti-hyaluronidase activity. EGCG also exhibited dose dependent (r2=0.93, P<0.05) anti-hyaluronidase activity which was superior [IC50=(0.09±0.00) mg/mL] to BTB. Conclusions: Sri Lankan low grown orthodox OP grade black tea has promising anti-hyaluronidase activity in vitro and has the potential to be used as an anti-aging cosmaceutical. In addition, it may prove useful as a beverage in the management of allergy, some joint diseases and envenomation