Pyrrolizidine-producing weeds in tea gardens as an indicator of alkaloids in tea

ABSTRACT

Pyrrolizidine alkaloids (PAs) can be transferred between plants via soil. Indicators of PAs in tea products are useful for tea garden management. In the present work a total of 37 weed species, 37 weed rhizospheric soils and 24 fresh tea leaf samples were collected from tea gardens, in which PAs were detected in 35 weeds species, 21 soil samples and 10 fresh tea leaves samples. In Shexian tea garden, 12.9 μg/kg of intermedine (Im) in one bud plus three leaves, 1.40 and 14.6 μg/kg of intermedine-N-oxide (ImNO) in one bud plus two leaves and one bud plus three leaves were detected, which were transferred from the PA-producing weeds via soil. However, no PAs were detected in fresh tea leaves collected from Langxi tea garden. The results indicated that synthesis of PAs in weeds and their transfer through the weed-soil-fresh tea leaf route varied with soil environments in different tea gardens.

KEYWORDS:

• Contamination
• pyrrolizidine alkaloids
• tea
• tea garden
• weeds
• soil

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the National Natural Scientific Foundation of China [32102244], National Agricultural Products Quality and Safety and Risk Assessment Project [GJFP2020001 and GJFP2021001], Natural Scientific Foundation of Anhui Province [19252002], Department of Science and Technology of Anhui Province [202103b06020024 to YT], and the USDA [HAW05020H].