Common madder (Rubia tinctorum L.) produces anthraquinone pigments in its roots, one of them being alizarin (1,2 dihydroxy anthraquinone) which has been used for dyeing textiles since 2000 B.C. Four madder genotypes were evaluated for their agronomic characteristics as well as for their industrial value in order to test this species domestication potential for the Mediterranean area and to assess its value as a new industrial dye crop. Pigments were separated from methanolic and ethereal extracts and quantified by HPLC. Good agronomic performance was observed in the different accessions of R. tinctorum which were tested. Root yield increased from young (5 months old) to mature plants (30 months old) reaching a mean value of 120 g plant-1, which corresponds to a yield of 8 t ha-1. Variation in yield capacity was observed among the different accessions. Young roots showed a higher alizarin content than 15 and 30 month old plants. However, the total amount of alizarin present in a plant increased from 181.8 mg plant-1 to 917.8 mg plant-1 in 5 to 30 month old plants. A range of variation in alizarin content was established for genetic differences within madder. Industrial assays demonstrated good performance when using a weight of dry powder which is 30% of the weight of material to be dyed for dyeing cotton, wool and silk yarns. Resistance to fading appears to be fairly good for dyed wool.
Rubia tinctorum L.: a source of natural dyes: agronomic evaluation, quantitative analysis of alizarin and industrial assays
ANGELINI, LUCIANA GABRIELLA;PISTELLI, LUISA;BERTOLI, ALESSANDRA;
1997-01-01
Abstract
Common madder (Rubia tinctorum L.) produces anthraquinone pigments in its roots, one of them being alizarin (1,2 dihydroxy anthraquinone) which has been used for dyeing textiles since 2000 B.C. Four madder genotypes were evaluated for their agronomic characteristics as well as for their industrial value in order to test this species domestication potential for the Mediterranean area and to assess its value as a new industrial dye crop. Pigments were separated from methanolic and ethereal extracts and quantified by HPLC. Good agronomic performance was observed in the different accessions of R. tinctorum which were tested. Root yield increased from young (5 months old) to mature plants (30 months old) reaching a mean value of 120 g plant-1, which corresponds to a yield of 8 t ha-1. Variation in yield capacity was observed among the different accessions. Young roots showed a higher alizarin content than 15 and 30 month old plants. However, the total amount of alizarin present in a plant increased from 181.8 mg plant-1 to 917.8 mg plant-1 in 5 to 30 month old plants. A range of variation in alizarin content was established for genetic differences within madder. Industrial assays demonstrated good performance when using a weight of dry powder which is 30% of the weight of material to be dyed for dyeing cotton, wool and silk yarns. Resistance to fading appears to be fairly good for dyed wool.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
