Organ-specific bioactivity and mineral profiles of Camellia sinensis across contrasting plantations in the Georgian Caucasus

Tea processing targets leaves, whereas fruit shells and seeds are typically discarded. This is the first regional study in the Georgian Caucasus, providing a comprehensive dataset from Georgian tea plantations. Using plantations from the Georgian Caucasus as a contrasting field setting, we assessed the mineral composition, polyphenols, antioxidant capacity, and carbohydrase-inhibitory activity of Camellia sinensis leaves, fruit shells, and seeds. We explored the co-variation between soil and plant. UPLC-MS/MS profiled polyphenols; minerals by ICP; antioxidant capacity by ABTS, DPPH, FRAP, and ORAC; α-amylase/α-glucosidase inhibition was expressed as IC₅₀. Leaves were catechin-rich (e.g., gallocatechin gallate up to 1140 mg/100 g dry matter (dm) and showed moderate antioxidant values, with the strongest α -amylase inhibition (IC₅₀ 6.10–8.60 mg/mL). Fruit shells, a processing by-product, exhibited the highest antioxidant capacity (e.g., FRAP 249–297; ORAC 315–344 μmol Trolox/g dm) and elevated Mn (167–223 mg/kg dm), yet no detectable carbohydrase inhibition. Seeds were enriched in apigenin C-glycosides (283–286 mg/100 g dm), presented the lowest IC₅₀ for α-glucosidase (1.92–2.25 mg/mL), and contained high K (0.80–1.25 g/100 g dm) with no detectable Pb, Al, Cd, or Ni. Multivariate analyses indicated a polyphenol–antioxidant axis and a K/Mg–enzyme association (co-variation, not causation). These findings reveal distinct, organ-specific functionalities and support zero-waste valorization, with fruit shells serving as antioxidant sources and seeds as candidates for modulating starch digestion. The results motivate replicated, multi-site work to disentangle the impact of soil versus management on scale extraction/utilization pathways for industrial applications. These findings provide the first regionally comprehensive insight into the functional and compositional diversity of Georgian tea plantations, supporting zero-waste valorization strategies and motivating replicated, multi-site studies to clarify environmental and management influences. • Tea by-products contain valuable bioactive compounds for industry. • Georgian tea seeds are a rich source of apigenin. • Fruit shells show high antioxidant activity despite low polyphenols. • Soil elements influence bioactive accumulation in tea organs. • Tea waste valorization promotes sustainable, zero-waste crop use.