Carotenoid composition and vitamin A value of an Argentinian squash (Cucurbita moschata)

the carotenoid composition of butternut squash (cucurbita moschata) cultivated in the province of santiago del estero, argentina, was determined. the main carotenoids isolated were identified as b -carotene (b ,b -carotene), a -carotene (b ,e -carotene), and lutein (b ,e -carotene-3,3？-diol) and the minor carotenoids, as phytofluene (7,8,11,12,7？,8？-hexahydro-y ,y -carotene), z -carotene (7,8,7？,8？-tetrahydro-y ,y -carotene), neurosporene (7,8-dihydro-y ,y -carotene), violaxanthin (5,6,5？,6？-diepoxy-5,6,5？,6？-tetrahydro-???-carotene-3,3？-diol) and neoxanthin (5,6-epoxy-6,7-didehydro-5,6,5？,6？-tetrahydro-b ,b -carotene-3,5,3？-triol). in some samples, 5,6,5？,6？-b -carotene diepoxide, (5,6,5？,6？-diepoxy-5,6,5？,6？-tetrahydro-b ,b -carotene) and flavoxanthin (5,8-epoxy-5,8-dihydro-b ,e -?carotene-3,3'-diol) were detected. the presence of cis-isomers of -b ,b -carotene was also detected by hplc. the vitamin a value obtained was 432 ?g re/ 100g fresh sample, which indicates that this vegetable is an important source of provitamin a