Characterisation of purple acid phosphatase from breadfruit (Artocarpus communis) seeds

ABSTRACT Objectives: To investigate the biochemical properties, physiological role and possible application of a purple acid phosphatase isolated from breadfruit (Artocarpus communis) seeds. Methodology and results: An acid phosphatase was purified 13.7-fold to apparent homogeneity from breadfruit (Artocarpus communis) seeds, using successive chromatographies on DEAE-Sepharose Fast-flow, Sephacryl S-100 HR, and phenyl Sepharose 6 Fast-flow. The enzyme was a purple acid phosphatase (λmax = 510 nm) that appeared to be a monomeric protein with molecular weight of approximately 27.3 kDa by SDS PAGE. The purple acid phosphatase was optimally active at pH 5.5 and 55°C, but strongly inhibited by molybdate, vanadate, phosphate and zinc. Moreover it did not require divalent cations for catalysis. This phosphatase showed wide substrate specificity with high affinity for sodium pyrophosphate, suggesting that pyrophosphate could be its potential physiological substrate. The enzyme also hydrolyzed sodium phytate. Potential application of finding: The purified enzyme could be applied in the mineral fertilizers industry or as a food additive for monogastric animals, e.g. pigs, in farming systems