“…However, found many restrictions were found for the approval and acceptance of these substances as a health-promoting supplement in various countries since these compounds e.g., propolis products are not standardized and vary in their components and biological activity among countries and even at a regional level, and therefore, faced many relevant criticism ( Bankova, 2005 ; Toreti et al, 2013 ; Miguel et al, 2014 ). However, it should be stressed that standardized propolis products e.g., standardized Brazilian propolis extract blend have recently become available to overcome this major drawback and showed higher safety profile and major effectiveness for treatment of many pathological conditions ( Berretta, 2007 ; Berretta et al, 2012 ; Berretta et al, 2017 ; Silveira et al, 2019 ; Zaccaria et al, 2019 ). Therefore, standardized propolis is considered an example for natural products that can be used a nutraceutical or functional food resource that might provide a promising safe and easy to administer therapeutic for fighting COVID-19 pandemic ( Fielding et al, 2020 ).…”