From waste to health: a review on benefits of certain food by-products

Abstract

Nearly one-third of the food produced worldwide is wasted or lost annually, resulting in serious adverse impacts on the society, environment, and economy. Owing to the magnitude of this crisis, the United Nations has established a worldwide objective to halve food loss and waste by 2030. Certain food by-products cannot be considered garbage due to their valuable nutritional or health benefits, which can be invested in the pharmaceutical industry. This review is a concerted effort to identify the major active constituents and biological activities of various food by-products. We selected the by-products generated from eggplant, taro, okra, and coconut based on their promising phytochemical and biological findings in literature and market availability. All these by-products have in common that they are rich in phenolic compounds, which make them biologically effective as antioxidant, anti-inflammatory, and anti-cancer agents. According to their biologically active compounds, by-products of eggplant, taro, okra, and coconut are superb sources of anthocyanins, luteolin, quercetin, and catechins, respectively. In addition, the presence of chlorophyll in certain food by-products, with higher concentration in plant leaves compared to other parts, exerts valuable health benefits, such as anti-oxidant, anti-mutagenic, and anti-genotoxic activities. According to the medicinal, environmental, and economic benefits of the utilization of certain food by-products, we conclude that there are chances for more phytochemical, biological, industrial, and clinical investigations to encourage their use as a renewable raw material in pharmaceutical products.