Lithium biofortification of medicinal tea Apocynum venetum.

Lithium (Li) could be much safer and successful approach to supply Li via Li-fortified food products. This study is highlighting the potential scope of Li supply via Li-biofortification of Luobuma tea (made from Apocynum venetum leaves), which is a very popular beverage in Asia with several medical properties. We explored the possibility of A. venetum as Li-enriched tea and investigated plant growth, Li accumulation, total flavonoids (TFs), rutin and hyperoside concentrations, and the antioxidant capacity of A. venetum. With the increase of additional Li, Li concentration in roots, stems and leaves increased gradually. Compared with the control treatment, 10-15 mg kg^-1 Li addition stimulated the growth of A. venetum and 25 mg kg^-1 Li addition significantly increased the Li concentration in leaves by 80 mg kg^-1. Li application did not decrease TFs, rutin, hyperoside and antioxidant capacity of this medicinal herb. A daily consumption of 10 g Li-biofortified A. venetum leaves (cultivated with 25 mg kg^-1 LiCl) can give 592 μg Li intake and would constitute 59% of the provisional recommended dietary daily intake of Li. Our results showed that Li-biofortified A. venetum leaves can be used as Li-fortified tea to enhance Li supply and to improve human health when it was used as daily drink.