A Dissipation Pattern of Gibberellic Acid and Its Metabolite, Isogibberellic Acid, during Tea Planting, Manufacturing, and Brewing

Abstract

As a widely used plant growth regulator, the gibberellic acid (GA 3 ) residue in tea has potential risk for human health. Herein, the degradation of GA 3 and its conversion into main metabolites were investigated during tea planting, manufacturing, and brewing using ultrahigh-performance liquid chromatography tandem mass spectrometry. The metabolite iso-GA 3 was first discovered during the tea production chain and identified using Q-Exactive Orbitrap mass spectrometry. GA 3 dissipated following first-order kinetics in tea shoots with half-lives ranging from 2.46 to 2.74 days. It was degraded into iso-GA 3 in tea shoots, which had a longer residual period than GA 3 . Meanwhile, external application of GA 3 could increase the proportion of growth-promoting endogenous phytohormones and lead to rapid growth of tea plants. During tea manufacturing, iso-GA 3 was quickly and massively converted from GA 3 . Fixing (heat at 220−230 °C) played an important role in the dissipation of GA 3 and iso-GA 3 during green tea manufacturing, but there were high residues of iso-GA 3 in black tea. High transfer rates (77.3 to 94.5%) of GA 3 and iso-GA 3 were observed during tea brewing. These results could provide a practical reference for food safety in tea and other agricultural products and the guidance for scientific application of GA 3 in tea planting.

(+)‐Catechin, epicatechin and epigallocatechin gallate are important inducible defensive compounds against Ectropis grisescens in tea plants

“…JA, JA‐Ile and SA were quantified according to a method described in J. Lu et al (2015). IAA, ABA and GA7 were quantified according to a method described in Jiang et al (2020). The contents of JA, JA‐Ile, SA, GA7 and IAA were quantified using an internal standard curve, while the content of ABA was quantified using an external standard curve.…”

Impacts of n‐acetyl cysteine on gibberellic acid‐induced hepatorenal dysfunction through modulation of pro‐inflammatory cytokines, antifibrotic and antioxidant activity

“…NAC preserves and enhances the livers and kidneys' ability to eliminate heavy metals (Beyaz et al, 2011). GA3 residues as a result of the ingestion of some types of fruit and plant contribute to significant health risks (Jiang et al, 2020). GA3 is known to influence the antioxidant systems and development of free radicals (Celik et al, 2006).…”

Detection methods, migration patterns, and health effects of pesticide residues in tea

“…From dry tea to brewing tea, the immersion factor of carbendazim was greater than 0.8, and most carbendazim in dry tea would enter the tea soup. In another study, Jiang et al (2020) explored the dissipation pattern of gibberellin (GA3) and its metabolite, and the t 1/2 of GA3 in tea plant growth is 2.46-2.74 days. Meanwhile, GA3 can be easily converted to iso-GA3, and iso-GA3 is more stable than GA3 in tea planting and processing, which will bring new safety risks (Chen et al, 2013).…”