{Reference Type}: Journal Article {Title}: Potentialities of Tannase-Treated Green Tea Extract in Nutraceutical and Therapeutic Applications. {Author}: Ong CB;Annuar MSM; {Journal}: Appl Biochem Biotechnol {Volume}: 0 {Issue}: 0 {Year}: 2024 May 7 {Factor}: 3.094 {DOI}: 10.1007/s12010-024-04946-y {Abstract}: Green tea has garnered widespread interest in the past decades due to its content of health-beneficial polyphenols and catechins, besides reportedly exhibiting activities for the prevention, and possibly treatment, of many modern-life-associated afflictions. Hence, the functional food potential of health-beneficial beverages such as green tea is widely and commercially promoted. Biotransformation of green tea extract using enzymes such as tannase ostensibly enhances its beneficial well-being properties and disease-preventing functionalities. The tannase-treated green tea catechins may exhibit enhanced, amongst others, antioxidant, anti-tumour, anti-wrinkle, anti-inflammatory, anti-obesity and anti-sarcopenia properties compared to native green tea extract. Nonetheless, the health benefits and therapeutic and toxicological effects associated with these compounds, before and after tannase treatment, present a scientific gap for detailed studies. Accordingly, the review surveys the literature from the late twentieth century until the year 2023 related to the aforementioned important aspects.