Potential use of tea extract as a complementary mouthwash: comparative evaluation of two commercial samples.

OBJECTIVE: To evaluate the potential of using tea extracts as complementary mouthwash and to test the comparative efficacy of two commercial samples. DESIGN: A randomized controlled trial with 30 healthy human volunteers was carried out. The subjects were randomly assigned to 5 groups of 6 subjects per group. The ability of Ndu tea (from Cameroon) and Lipton tea (from Nigeria) to reduce colony forming units (CFU) in the liquid expectorated after 60 seconds of gargling from the mouth of the volunteers at 5 and 60 minutes were evaluated. These were compared to the values obtained from bank water and Minty Brett (thymol 0.047%), a standard antiseptic. SETTING: University of Nigeria, Nsukka, Enugu State, Nigeria. SUBJECTS: Thirty healthy human volunteers (18 males and 12 females, between 22-30 years of age) who met the eligibility requirement of being nonsmokers and not taking any other antimicrobial agent were selected for the study. RESULT: Relative to the bank water, the results indicated that the hot water extract of both teas significantly (p < 0.05) reduced CFU per milliliter in the liquid expectorated after gargling at both 5 and 60 minutes. Minty Brett showed higher activity than both tea extracts; however, unlike Minty Brett both extracts still reduced the CFU per milliliter at time 60 minutes (an indication of longer duration of activity). The combination of the tea extracts with sodium lauryl sulfate (1.2% w/v), a surfactant and emulsifier, significantly increased the antimicrobial activity relative to each tea alone. Comparatively, the activity of Ndu tea was found to be slightly higher than that of Lipton tea but this was not significant (p < 0.05). CONCLUSION: Lipton and Ndu tea extracts potently reduced the CFU per milliliter. This activity was potentiated by sodium lauryl sulfate. Although Minty Brett had more potent antimicrobial activity, both tea extracts have longer duration of activity. The results indicate the potential usefulness of tea extracts as a complementary mouthwash.

Analgesic effect of Irvingia gabonensis stem bark extract.

Irvingia gabonensis is used medicinally in most parts of tropical Africa for the treatment of a number of ailments. In West Africa the Mende tribe of Sierra Leone uses the stem bark to relieve pain. In order to establish a pharmacological rationale for the traditional use of this plant as a remedy for pain, the water and ethanol extracts of the powdered stem bark were screened for analgesic activity and compared with standard analgesic drugs. The water extract and morphine protected the mice from heat-induced pain. In contrast, the ethanol extract and metamizole sodium showed very low level of analgesic activity in this test. However, using tail pressure as a source of pain, the water and ethanol extracts, metamizole sodium and morphine offered protection to the mice against pain stimuli. Morphine and the water extract were more potent as analgesic agents in heat than non-heat pain test. The analgesic effects of the water extract and morphine were blocked by a non-selective opioid receptor antagonist, naloxone in both tests, whereas the analgesic effects of the ethanol extract and metamizole sodium were not antagonized by the same dose of the opioid antagonist. The data presented in this study suggest that the active principle(s) in the water extract has analgesic profile similar to that of the narcotic analgesic and the ethanol extract might contain compound(s) that behave like non-narcotic analgesic agent. These findings provide for the first time the pharmacological basis for the folkloric use of Irvingia gabonensis in the relief of pain.