Fig. 1
From: A catechol-type lignan and neolignans are specifically present in the seed coat of tung trees
The developmental stages of tung tree fruits. From left, stage 1 (immature green): green fruits about 4.5 cm in diameter, 4 months after anthesis. Stage 2 (mature green): green fruits about 6 cm in diameter, 5 months after anthesis. Stage 3 (turning): red brown fruits about 6 cm in diameter, 5 months after anthesis. Stage 4 (over ripe): brown fruit about 6 cm in diameter, 5 months after anthesis