Investigation on the enzymatic potential of oleaginous cucurbit (Lagenaria siceraria round-fruited cultivar) seeds led to purification of two acid phosphatases named RLsAP1 and RLsAP2. Properties of these enzymes were examined in order to explore their potential in biotechnology applications. A four steps procedure including, anion and cation exchange, size exclusion and hydrophobic interaction chromatography were used for purification. The enzymes had native molecular weights of approximately 70 and 55 kDa, respectively and functioned both as dimeric structures. The two phosphatases displayed acidic and mesophilic activities by using para-nitrophenylphosphate as a substrate. Their activities were enhanced by Mg2+, K+ and ethylene diamine tetraacetic acid (EDTA). Substrate specificity indicated that the two enzymes hydrolyzed a broad range of phosphorylated substrates mainly consisting of adenosine-5’-triphosphate (ATP) and adenosine-5’-diphosphate (ADP) hydrolysis. Furthermore, the purified acid phosphatase RLsAP1 exhibited an interesting phytasic activity. These results suggest that the two purified acid phosphatases might play an important role in energy transfer, releasing of inorganic phosphate and in reducing the rate of phytate, an antinutrient contained in this plant seeds. RLsAP1 could find potential use in both human food and animal feed.

Key words: acid phosphatase, Cucurbitaceae edible seeds, Lagenaria siceraria round-fruited cultivar, phytasic activity