The Elements Defining the Potential for the Development of Health-Promoting Substances from Secondary Herbal Materials

Agricultural waste is rich in bioactive molecules. When evaluating the viability of circular models for the development of health-promoting substances and final products, it is important to highlight that the industrial processing of fruits and other valuable herbal materials generates a considerable number of by-products and significant amounts of waste that contain health-promoting components. These by-products can be utilized purposefully in pharmaceuticals and related areas for the development of health-promoting products. The linear utilization of agricultural waste results in the loss of a range of valuable bioactive compounds, including polyphenols (anthocyanins, flavonoids, phenolic acids, and related compounds), antioxidants from other groups, phytosterols, tocopherols, and fatty acids. As an illustrative example, the waste materials of species belonging to the <i>Vaccinium</i> L. genus represent a notable secondary resource that can be purposefully applied to the development of health-promoting preparations. The fruits of these wasted herbal materials have been found to contain beneficial polyphenols, which play a pivotal role in the prevention of various chronic conditions, including precancerous conditions, inflammatory diseases, and other ailments. In addition, the fruits of blackberries, elderberries, and purple corn—which are similarly rich in anthocyanins—also provide a promising avenue for further development. Phenolic compounds suitable for recycling are also found in the by-products of sugarcane harvesting. Tomato waste contains a significant amount of lycopene, which is a valuable carotenoid. Other physiological functions may be attributed to the aforementioned by-products of fruit processing which, if used properly, can contribute to the prevention of certain diseases and improving quality of life. This review assesses the gaps in the existing literature on the development of health-promoting substances from herbal secondary materials.