Study on FTIR spectroscopy, total phenolic content, antioxidant activity and anti-amylase activity of extracts and different tea forms of Garcinia schomburgkiana leaves

Abstract

The differentiation of extracts and tea forms obtained from Garcinia schomburgkiana leaves helped to deeper understand of impact of tea infusion on biological activity. This study indicated major components, such as carbohydrates, lipids, fatty acids, proteins, amino acids, phenyl groups, alcohol, and isoprenoids in the extracts and different tea forms. The result showed that ethanol extract revealed significantly the strongest total phenolic content and antioxidant activity. Powder tea from old leaf showed significantly the highest total phenolic content and antioxidant activity at 3 and 5 min infusion time, while old leaf tea showed the highest amylase inhibition at 7 min. Interestingly, very strong positive correlation between total phenolic content and antioxidant activity, between FTIR spectra and total phenolic contents, and between FTIR spectra and antioxidant activity was found, significantly. Combining FTIR, PCA and cluster analysis obtained from the biological assays and FTIR data separated reliably ethanol extracts from other samples. © 2020 Elsevier Ltd