Improved liquid chromatographic method for determination of carotenoids in Taiwanese mango (Mangifera indica L.)

An HPLC method was developed to determine the various carotenoids in Taiwanese mango (Mangifera indica L.). Initially, the peel and seed of mangoes were removed, the pulps were cut into pieces, freeze-dried, ground into powder, extracted and subjected to HPLC analysis. A mobile phase of methanol-isopropanol (99:1, v/v) (A) and methylene chloride (100%) (B) with the following gradient elution was developed: 100% A and 0% B in the beginning, maintained for 15 min, decreased to 70% A in 45 min, maintained for 15 min and returned to 100% A in 65 min. A total of 25 carotenoids were resolved within 53 min by using a C-30 column with flow rate at 1 mL/min and detection at 450 nm. alpha-Carotene was used as an internal standard to quantify all the carotenoids. All-trans-beta-carotene was present in largest amount (29.34 microg/g), followed by cis isomers of beta-carotene (9.86 microg/g), violaxanthin and its cis isomers (6.40 microg/g), neochrome (5.03 microg/g), luteoxanthin (3.6 microg/g), neoxanthin and its cis isomers (1.88 microg/g), zeaxanthin (1.16 microg/g) and 9- or 9'-cis-lutein (0.78 microg/g).