Food Science and Technology International | 2021
Correlation of anti-wrinkling and free radical antioxidant activities of Areca nut with phenolic and flavonoid contents
Abstract
Free radicals, including reactive oxygen species (ROS) and reactive nitrogen species (RNS) are molecules that have unpaired electrons. They are generally unstable and damage normal cells in the body (Kim et al., 2018). These free radicals can be produced by environmental pollution, chemicals, UV rays, and stress in living organisms (Figure 1). When a certain amount of ROS and RNS are produced in the body, they are removed by antioxidant mechanisms of endogenous antioxidant enzymes, such as catalase (CAT), glutathione peroxidase (GSH-Px), and superoxide dismutase (SOD) (Choi et al., 2004; Park et al., 2017). However, excessive amounts of ROS (hydrogen peroxide H2O2, superoxide anion O2 -, and hydroxyl radicals OH) and RNS (peroxynitrite ONOOand nitroxyl anion NO·) produced by cellular metabolism may attack biological tissues and damage cells during various metabolic processes (Yun et al., 2018; Lee & Im, 2012). ROS and RNS have been reported to cause oxidative stress on proteins and DNA in cells that can lead to cell damage, and may contribute to degenerative diseases, such as meningitis, Alzheimer’s disease and Parkinson’s disease (Yun et al., 2018; Lee & Im 2012). In addition, they are involved in promoting melanin production by destroying and damaging the skin’s antioxidant defense network, which can lead to accelerated skin aging, such as wrinkle formation, elasticity reduction, freckles, and spotting (Go et al., 2020). The safety problems related to synthetic antioxidants (BHA, BHT, and others) have led to an increased interest in the development of safe and inexpensive natural-product antioxidants (Park & Kim, 2008). The polyphenols and flavonoids of natural antioxidants are known to possess strong antioxidant activities, and have the ability to scavenge ROS, RNS, and free radicals. Moreover, several studies have reported a correlation between the increased dietary intake of natural antioxidants and a reduction in coronary heart disease, reduced cancer mortality, anti-aging, and longer life extension (Cho et al., 2016).