Luteolin: A flavone with myriads of bioactivities and food applications

Flavonoids are increasingly applied in foods to promote their functional properties, human health, and overall wellbeing. Luteolin, a polyphenolic plant flavonoid, is recognized as one of the plausible bioactive components that can be notably intriguing for food applications and for fabricating active packaging systems with antimicrobial properties. Luteolin is a flavone-based polyphenol naturally found as glycosides, with a phenylpropanoid biosynthesis route. Luteolin, when ingested and absorbed in the intestine, converts from free to conjugated-form, thereby forming luteolin glucuronides, which are presumably responsible for a range of luteolin bioactivities. Owing to these health-promoting potentials, along with ease of delivery, exceptional applications, and negligible toxicity, an integral valorization approach involving sustainable technologies to recover these high-value-added ingredients and their utilization should be further stimulated. This is the first review that seeks to thoroughly compile some of the important data published on biosynthesis, mechanism of action, bioactivities, bioavailability, and toxicity potential of luteolin.