colorant
Genipin
A colorless iridoid compound reported to occur in the unripe fruit of jenipapo. It is said to react spontaneously with primary amines, including proteins, to form a blue pigment (described as a mixture of high-molecular-weight polymers).
Theme: Bonding
Claims and evidence (5)
The limitations noted for some sources are recorded in Japanese only — see the Japanese edition.
Genipapo (jenipapeiro) produces Genipincontextual
States the fruit contains numerous iridoid compounds, and that geniposide and its aglycone genipin are the substances indigenous peoples found could colour and tattoo skin black.
Source: A beleza invisível da biodiversidade: genipina, o principio ativo do preto das pinturas no corpo de índios brasileiros （Vanderlan Bolzani, 2016） ・図7・図8を説明する段落（『O jenipapo contém uma série de substâncias...』以降） ・journalistic report ・ checked against the source by AI
journalistic report ・ 
checked against the source by AIGenipin ・mechanismThe spontaneous reaction of primary amines — including proteins — with genipin is reported to form a blue pigment, described as a mixture of high-molecular-weight polymers. This reaction is said not to occur with secondary or tertiary amines, and oxygen is reported to be indispensable for the blue colour to form.contextual
States the spontaneous reaction of primary amines (including proteins) with genipin forms a blue pigment (a mixture of high-molecular-weight polymers), does not occur with secondary or tertiary amines, and requires oxygen for the colour to form.
Source: Obtenção de corante natural azul extraído de frutos de jenipapo （Isis Rodrigues Toledo Renhe, Paulo César Stringheta, Fabyano Fonseca e Silva, Taila Veloso de Oliveira, 2009） ・p.649（Touyama et al. 1994bを引用する段落） ・analytical ・ checked against the source by AI
analytical ・ Genipin ・mechanismFormation of the blue pigment is reported to pass through yellow intermediate compounds, which are in turn precursors of further reddish-brown intermediates. Given these reaction conditions, this source states that the blue pigment is thought to form through oxygen-radical-induced polymerization and dehydrogenation of the intermediate pigments.contextual
States blue-pigment formation passes through yellow intermediates that are precursors of reddish-brown intermediates, and is thought to occur via oxygen-radical-induced polymerization and dehydrogenation.
Source: Obtenção de corante natural azul extraído de frutos de jenipapo （Isis Rodrigues Toledo Renhe, Paulo César Stringheta, Fabyano Fonseca e Silva, Taila Veloso de Oliveira, 2009） ・p.649（Touyama et al. 1994a, 1994bを引用する段落） ・analytical ・ checked against the source by AI
Genipin ・propertyGenipin is reported to be colourless early in the fruit's development, and to lose its colouring effect once the fruit ripens.contextual
States genipin is colourless early in fruiting and loses its colouring effect after ripening (citing Corrêa 1969 and others).
Source: A beleza invisível da biodiversidade: genipina, o principio ativo do preto das pinturas no corpo de índios brasileiros （Vanderlan Bolzani, 2016） ・図8の説明文の直後の段落 ・journalistic report ・ checked against the source by AI
Genipin ・propertySeveral 16th-17th-century chroniclers — Hans Staden (1557), Gabriel Soares de Sousa and Fernão Cardim (1585), and Willem Piso (1648) — are reported to have described, in almost identical words, that the colourless iridoid (genipin) turned black once applied to skin, matching the colour seen in indigenous body tattoos. This source suggests they may have been among the first to record this colour-change.contextual
States multiple chroniclers in 1557, 1585 and 1648 described in nearly identical words how the colourless iridoid turned black on skin, similar to indigenous tattoos, and suggests they may be among the earliest such records.
Source: A beleza invisível da biodiversidade: genipina, o principio ativo do preto das pinturas no corpo de índios brasileiros （Vanderlan Bolzani, 2016） ・図8説明文の段落（Hans Staden, Gabriel Soares de Sousa, Fernão Cardim, Wilen Pisoに触れる箇所） ・journalistic report ・ checked against the source by AI