Valorization of coffee leaves as a potential agri‑food resource: bio‑active compounds, applications and future prospective.

Coffee leaves have been processed for herbal tea and ethno-medicine since centuries in the parts of the world where
coffee is grown traditionally. Currently, interest in the valorisation of coffee leaves for its application in the food industry is
proliferating and the research related to it is scanty and, therefore, worthwhile to congregate. The current review compromises
the botanical description, chemical composition, bio-actives and ethnomedicinal properties of coffee leaves. It encompasses
the existing pharmacological studies on coffee leaves including the anti-oxidant, anti-inflammatory and anti-obesity activities
to pave path for future research. Furthermore, applications and patents associated with coffee leaves in different fields
such as therapeutic agents, beverages, packaging material, tobacco substitute etc. have been summarized. The investigation
reveals that, despite of many patents on coffee leaves only few products could reach the worldwide market; also in spite of
coffee leaves having a rich ethno-medicinal use the study on its pharmacological activities are scarce which creates a huge
scope to carry out in-vitro and in-vivo research on its various bio-activities. Future insights reflecting the supplementary
research regarding the sensory attributes, changes in phytochemical composition, flavour development and product formulations
which is vital are also discussed. In conclusion, this review addresses the breach and specifies the requirements to
convert the existing knowledge into commercialized food products with functional properties. Thus, coffee leaves being a
copious resource of bio-actives serve as a potential agri-food resource and a promising future in the emerging functional
food and nutraceutical industry.