Little information regarding the utilization of algal-based pigments in textile industry is available despite their abundance in aquatic ecosystems, varying color nature, and relatively fast-growing ...habit than other photosynthetic organisms. The aim of the current study is to optimize the conditions in order to harness the colorants from selected marine algal species and evaluating their dye yielding potential for fabric dyeing. Cotton fabrics were dyed with aqueous, alkaline, acidic or organic extracts of four algal species, the brown algae
Iyengaria stellata
,
Sargassum muticum
,
Colpomenia sinuosa
, and the red alga
Laurencia obtusa
under varying conditions of temperature, pH, and exhausting agent concentration. Results showed that 4% KOH and 80% acetone extraction produced maximum color strength of dyed cotton fabric. Among the four species of algae used in the study,
L. obtusa
showed the highest yield of colorant. However, all four species extract behaved differently to dyeing conditions. Mordanting experiments results revealed that iron sulphate and tannic acid were excellent pre- and post-mordanting agents for producing darker color shades of cotton fabrics dyed with all the four algal species used in the study. FTIR analysis indicated that the dominant coloring agents in all four algal species were phenolics in nature. The fabric dyed with extract of
I. stellata
,
C. sinuosa
, and
L. obtusa
showed creamy white shade, while
S. muticum-
treated fabric produced light brown shade. Pre- and post-mordanting of algal powder dyed fabric with chemical mordants, particularly the tannic acid produced other shades, such as light and dark brown.
Exploration of algal-based natural dye sources, one of the pre-requisites of sustainable and eco-friendly textile processing, had been among the neglected areas of phycological research. The current ...investigation was carried out to explore the natural dye-yielding potential of a green algal species,
Cladophora glomerata
, and optimization of conditions for cotton fabrics, as an attempt to provide a cheap alternative of hazardous synthetic chemicals. A number of media were tested to extract the natural colorant from
Cladophora
along with metal salts as mordants. The results indicated that 2% NaOH was the best medium for natural colorant extraction from
Cladophora
powder, compared with all other media used in the study. Experiments of dyeing variable optimization showed that dyeing of cotton fabric with
Cladophora
extract for 45 min at 75 °C produced excellent shades. Four percent NaCl as exhausting agent produced good color shades on
Cladophora
powder–treated cotton fabric in dyeing medium having pH 9.0. The cotton fabric dyed with
Cladophora
showed light-green color shade. Different other shades (creamy, yellow, brown, etc.) of
Cladophora
powder–treated cotton fabric were obtained after mordant application. Among the four chemical mordants, tannic acid produced excellent color depth at given optimum dyeing conditions.
