The anthocyanin compounds responsible for the deep pink color change in Lantana camara L. petals were investigated. The Lantana petals were categorized into four development stages (yellow, orange, pink, and deep pink) and extracted. Each extract contained three types of anthocyanins (PA–PC), which were mainly involved in the color change. The color change of the petals was predominately influenced by an increase in the total anthocyanin content and a higher proportion of PC. As an alternative strategy to obtain extraction sample consistently, irrespective of the seasons, in vitro calluses were induced from the Lantana petals to identify the structures of anthocyanins, and to understand the pigment metabolic capacity of petals. Callus growth with pigmentation occurred on the Murashige-Skoog medium supplemented with 5.0 µM 6-benzylaminopurine (BAP), 0.5 µM 2,4-Dichlorophenoxyacetic acid (2,4-D), and 1.0 µM α-Naphthalene acetic acid (NAA). The pigmented calluses contained the same three anthocyanins as petals. Compounds from callus extract, PA, PB, and PC were isolated. Structural analysis revealed PA, PB, and PC as cyanidin-3-O-glucoside, cyanidin-3-O-(6’’-O-malonyl)-glucoside, and cyanidin-3-O-(6’’-O-acetyl)-glucoside, respectively. Along with the development of petal color, a drastic increase in total anthocyanin content and the increase of ratio of anthocyanins that show longer wavelengths were confirmed, supporting the observed change in petal color change.
