Bioactive Compounds from Guava Leaves (Psidium guajava L.): Characterization, Biological Activity, Synergistic...

The characteristics of bioactive compounds from guava (Psidium guajava L.) leaf extract, their biological activity, and their technological applications are critical topics in many engineering fields. Guava leaf extract is rich in bioactive compounds, including phenolic acids, flavonoids, tannins, terpenes, alkaloids, etc. Bioactive compounds from guava leaf exhibit notable synergistic effects in enzyme inhibition, as well as antimicrobial and anti-inflammatory activities. Natural bioactive compounds are complicated due to their sensitivity and instability during storage, but their use is promising. Thus, for bioactive compound protection, advanced techniques such as the encapsulation, microemulsion, and nanosuspension of such natural bioactive compounds can be a promising approach. These methods are particularly important for the development of natural preservatives serving as additive agents, which have significant industrial relevance. However, sufficient scientific evidence is required to make a health claim on and to promote the functional benefits of guava leaf extract. This review focuses on recent research into guava leaf extract and its technical roles. Demonstrations of the chemical structure of bioactive compounds are addressed, besides discussing their analytical methods, nutritional bioavailability, biological activity, and synergy effects. Furthermore, this review study considers the methods used to protect the active compounds and technological applications in food, pharmaceuticals, and cosmetic products.