Phytosterols and squalene as hypocholesterolemic substances in five varieties of Cucurbita maxima and Cucurbita moschata (pumpkin) seeds [Fitoesteroles y escualeno como hipocolesterolémicos en cinco variedades de semillas de Cucurbita maxima y Cucurbita moschata (calabaza)]

Abstract

Introduction: the pumpkin seed has been studied and used in the treatment of parasitic diseases, benign prostatic hypertrophy, cystitis and as hypoglycemic substance. However, the research concerning the use of pumpkin seeds and especially the sterols and squalene as hypocholesterolemic elements in humans is unknown. Objective: to determine the phytosterol and squalene content of five varieties of umpkin seeds for their potential use as hypocholesterolemic compounds in humans. Methods: the pumpkin seeds from two species called Cucurbita maxima and Cucurbita moschata from Cuba and Mexico were studied. The varieties were Fifi, Marucha, INIVIT C-88 (Cuban), Tapatía and Chata (Mexican) for which the profile of phytosterols (beta-sitosterol, campesterol, stigmasterol and stigmastenol) and the squalene were determined using gas-liquid chromatography. Results: the content of ethereal extract and real fat in the seeds ranged 331.5 to 346, and 307 to 336 g/kg, respectively. The variety Fifi (C. moschata) had the highest content of unsaponifiable material (35.0 g/kg) and showed significant differences (p< 0.001) compared with other varieties and above that of conventional oilseeds. The squalene, and beta-sitosterol concentration was higher Marucha (Cucurbita moschata) (40.27 and 202.59 mg/100 g), indicating significant differences (p< 0.001) compared with other varieties. Marucha and Chata varieties exhibited the highest campesterol content (50.08 and 49.31 mg/100 g, respectively), and the Marucha evidenced the largest concentration of stigmasterol and stigmastenol (1.75 and 28.63 mg/100 g); additionally, the amounts contained were above those of the common vegetable food in the diet. Conclusions: the results in phytosterol and squalene concentrations achieved in the studied varieties suggested that the pumpkin seeds be studied as a possible hypocholesterolemic substance for humans.