Phenolic compounds are important functional bioactive substances distributed in various food plants. They have gained wide interest from researchers due to their multiple health benefits. There are two forms of phenolic compounds: free form and bound form. The latter is also called bound phenolics (BPs), which are found mainly in the cell wall and distributed in various tissues/organs of the plant body. They can either chemically bind to macromolecules and food matrixes or be physically entrapped in food matrixes and intact cells. Various isolation methods, including chemical, biological, and physical methods, have been employed to extract BPs from plants. BPs have been shown to have strong biological activities, including antioxidant, probiotic, anticancer, anti-inflammation, antiobesity, and antidiabetic effects as well as beneficial effects on central nervous system diseases. This review summarizes research findings on these topics to help in better understanding of BPs and provide comprehensive information on their health effects.

Review of Distribution, Extraction Methods, and Health Benefits of Bound Phenolics in Food Plants.

https://repositorium.sdum.uminho.pt/bitstream/1822/60398/1/document_51725_1.pdf

Simultaneous production of lignocellulolytic enzymes and extraction of antioxidant compounds by solid-state fermentation of agro-industrial wastes

Microwave and enzyme co-assisted aqueous two-phase extraction of polyphenol and lutein from marigold (Tagetes erecta L.) flower

Kombucha fermentation enhances the health-promoting properties of soymilk beverage

Millet grains are small seeded Kharif crop used as food and feed. Due to presence of bioactive compounds and important minerals, millets have their own importance among cereal grains. Finger millet is a mixture of gallic acid; p-hydroxybenzoic acid; gentisic acid; caffeic acid; syringic acid; p-coumaric acid; sinapic acid; salicylic acid; trans-cinnamic acid. Foxtail millet contains gallic acid; p-hydroxybenzoic acid; vanillic; caffeic acid; chlorogenic acid; ferulic acid; sinapic acid and p-coumaric acid. Pearl millet possesses gallic acid; syringic acid; p-coumaric acid, ascorbic acid and ferulic acid. Little millet is rich in gallic acid; p-hydroxybenzoic acid; vanillic; caffeic acid; chlorogenic acid; ferulic acid; sinapic acid and p-coumaric acid. Thermal processing leads to oxidative degradation and depolymerization of bioactive constituents present in millets. Bioactive compounds like ascorbic acid and carotenoids are heat sensitive and could lose their activity upon processing especially thermal processing. Higher temperature resulted in decrease in p-coumaric acid (14.3–3.8 mg 100 g−1), ellagic acid (8.5–4.9 mg 100 g−1), caffeic acid (6.3–2.3 mg 100 g−), gallic acid (224–170 mg 100 g−1), hydroxybenzoic acid (2.3–0.6 mg 100 g−1), catechin (87.2–45.6 mg 100 g−1), ferulic acid (45.4–17.5 mg 100 g−1) and epicatechin (23.9–4.8 mg 100 g−1). Millet extracts contain specific compounds with bioactive properties, including antioxidant activity, the ability to protect DNA, anti-diabetic, anti-inflammatory and other health-promoting properties. Processing imparts specific flavor, improve texture, taste and shelf life of millets based food products. Millet grains are of great interest because of their agro-industrial importance, high nutritional value and bioactive constituents.

Sheng Wu

Papers

Enzymatic action mechanism of phenolic mobilization in oats (Avena sativa L.) during solid-state fermentation with Monascus anka.