The researchers studied different types of Chinese kale to see how much chlorophyll and carotenoids they contained in their leaves and stems. They found that the levels of these nutrients varied a lot between the different types of Chinese kale. One type, JL-03, had the highest amounts of chlorophyll and carotenoids in its leaves. Lutein was the most common carotenoid found in the plants. The leaves had more chlorophyll and carotenoids than the stems. The researchers also discovered that the differences in nutrients were mainly due to the part of the plant, not how mature it was or its flower color. They also found that chlorophyll and carotenoids were linked in the plants. These findings could help improve the nutrition of Chinese kale for people and guide future breeding efforts.