Phenolic compounds and antioxidant activities of tea-type infusions processed from sea buckthorn (Hippophaë rhamnoides) leaves

•Infusions were prepared from sea buckthorn leaves processed with different methods.•Phenolics, metal-chelating and antioxidative activities of infusions were studied.•Cultivar had major effect on phenolic compounds in sea buckthorn leaves.•Flavonol glycosides were more stable than ellagitannins during leaf processing.