Carotenoids, such as lutein and β-carotene are generally recognized as antioxidants. However, only β-carotene has the pro-vitamin A activity. This study determined lutein and β-carotene in Asian leafy vegetables using reversed-phase high pressure liquid chromatography (HPLC). The selected samples were Chinese mustard (Brassica juncea var. rugose), water spinach (Ipomoea aquatic), Chinese spinach (Amaranthus tricolor), coriander (Coriandrum sativum), Chinese flowering cabbage (Brassica parachinensis), Chinese broccoli (Brassica oleracea alboglabra) and Chinese white cabbage (Brassica chinensis). Carotenoids were extracted from samples into 5% (w/v) calcium carbonate and acetone. The extracts were then concentrated at 4 °C and filtered prior to HPLC analysis. The recoveries for β-carotene and lutein were 132% and 100%, respectively. The coefficient of variation for inter-variability study was < 3.8% and for intra-variability study < 11%. The range of β-carotene in the selected vegetables was 1974-6604 µg/100 g (wet weight basis), or 329-1101 µg/100 g retinol equivalent (RE). Measured lutein contents were between 694- 5919 µg/100 g. Chinese broccoli had the highest pro-vitamin A activity (1101 µg RE per 100 g). The β-carotene data reported here was useful for estimating the pro-vitamin A intake from consuming the Asian leafy vegetables.

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