Rooibos (Aspalathus linearis) and its Major Flavonoids — Potential Against Oxidative Stress-Induced Conditions

Abstract

Reactive species are products of normal cellular metabolism and may be deleterious or beneficialɡ At low/moderate concentrationsɢ reactive species are involved in physiological roles including cell signallingɢ defense against infectious agents and mitogenic responsesɡ Howeverɢ unbalanced defense mechanism of antioxidantsɢ overproduction of reactive species or incorporation of free radicals into the living system from the environment may result in oxidative stressɢ a deleterious process that can lead to damage of important cell structuresɢ including lipids and membranesɢ proteins and nucleic acidsɡ The role of oxida‐ tive stress as a contributing factor in the pathophysiology of various diseases is increas‐ ingly being recognizedɢ and augmenting the oxidative defense capacity of the cell through the intake of antioxidants as a way of preventing free radical-mediated cellular injuries is becoming a popular strategyɡ Much attention is being focused on the health beneficial role of phenolic phytochemicals derived from plantsɡ They are considered to play an important role as physiologically functional foods and for the prevention of clini‐ cal conditions related to oxidative stressɢ even though their modes of action may still not be fully understoodɡ Rooibos ɭAspalathus linearisɮ is a popular South African tisane en‐ joyed for its taste and aromaɡ Rooibos has been made in the Cederberg mountain region of South Africa for generations and has been used medicinally for alleviation of allergiesɢ asthmaɢ infantile colic and skin problemsɡ The potential antioxidativeɢ immune-modulat‐ ingɢ chemopreventive and chemotherapeutic actions of rooibos have been reported in several studiesɡ This review provides a comprehensive data on the current knowledge of the biological and chemotherapeutic activity of rooibos and its major flavonoidsɡ Most re‐ cent in vitro and in vivo ɭanimal and humanɮ studies were conducted with special atten‐ tion paid to clinical conditions in which oxidative stress has been implicatedɡ The conclusion described directions for future rooibos research to establish its activity and utility as a human chemopreventive and therapeutic agentɡ