Total Antioxidant Capacity and Total Phenolics Content of Phyllostachys Taxa Shoots

Abstract

Total phenolic content (TP) and total antioxidant capacity (AC) were analysed in shoots of Phyllostachys aureosulcata (PA), P. aureosulcata f. aureocaulis (PAA), P. aureosulcata f. spectabilis (PAS), P. bissetii (PB), P. flexuosa (PF), P. humilis (PH), P. iridescens (PI), P. nigra var. nigra (PNN), P. nigra var. henonis (PNH), P. mannii (PM), P. sulphurea var. sulphurea (PSS), P. violascens (PVI), P. viridiglaucescens (PVG), P. vivax f. aureocaulis (PVA), collected on four harvest dates. Both TP and AC were determined following three processing methods, fresh, boiled and pickled in shoots of PF. Comparative study of TP and AC in the above Phyllostachys species shoots has not been reported before. The highest TP (1,227.6 μg GA/ml) and AC (154.0 μg AA/ml) values were measured in fresh shoots and the lowest in pickled ones. The highest values of TP were measured in the case of PA (1,321.95 μg GA/ml). The other taxa followed in decreasing order: PF, PVI, PI, PAA, PB, PAS, PNN, PNH, PM, PH, PSS and PVA. The highest AC values were obtained in the case of PI (184.24 μg AA/ml). The other taxa followed in decreasing order: PA, PF, PSS, PNN, PNH, PVG, PB, PAA, PAS, PV, PVA, PM and PH. The highest TP values were measured in taxa harvested on the first collection date and the values consequently decreased in taxa collected at later harvest dates. Our findings suggest that the earlier harvest date, through the influence of lower temperatures, could enhance the phytochemical content of bamboo shoots.