Effects of green tea, black tea and rooibos on angiotensin-converting enzyme activity in healthy volunteers
2009 (English)In: in Planta Medica(ISSN 0032-0943), 2009, Vol. 75, no 9, 1030-1030 p.Conference paper (Refereed)
Tea has been reported to reduce cardiovascular mortality, but the mechanisms behind are largely unknown. The aim of this project was to investigate the effect of green tea (Japanese Sencha), black tea (Indian Assam B.O.P.) and Rooibos on angiotensin-converting enzyme and nitric oxide. Seventeen healthy volunteers received a single oral dose of either 400 ml green tea, black tea or Rooibos tea in a randomized three-phase cross over study. ACE activity and NO concentration were measured (at 0, 30, 60 and 180 minutes) in all phases. ACE activity was analysed with a commercial radioenzymatic assay. Nitrite was analysed as a marker of NO concentration. In addition ACE genotype was determined using a PCR method. Oral intake of a single dose of Rooibos significantly inhibited ACE activity, p<0.01 after 30 min and p<0.05 after 60 min. A significant inhibition of ACE activity was seen with green tea for the ACE genotype II (p<0.05), 30 minutes after intake of the tea and for the ACE genotype ID (p<0.05), 60 minutes after intake. A significant inhibition of ACE activity was also seen with Rooibos for the ACE genotype II (p<0.05), 60 minutes after intake. No significant effect on NO concentration was seen.
Place, publisher, year, edition, pages
2009. Vol. 75, no 9, 1030-1030 p.
Tea, angiotensin-converting enzyme, nitric oxide
Medical and Health Sciences
IdentifiersURN: urn:nbn:se:liu:diva-20327OAI: oai:DiVA.org:liu-20327DiVA: diva2:234027
On the day of the defence date the status of this article was Submitted.2009-09-042009-09-042011-03-31Bibliographically approved