Rubia cordifolia (Tamin, local name) produces anthraquinone reddish orange dyes in roots, stem an... more Rubia cordifolia (Tamin, local name) produces anthraquinone reddish orange dyes in roots, stem and leaves, which has been used for dyeing textiles since ancient times. Commercial sonicator dyeing with Rubia showed that pretreatment with biomordant, Eurya acuminata DC var euprista Karth. (Theaceae family) [local name, Nausankhee (Apatani tribe), Turku (Nyishi tribe) in 2%] shows very good fastness properties for dyed cotton using dry powder as 10% of the weight of the fabric is optimum. Use of biomordant replaces metal mordants making natural dyeing ecofriendly.
The local natural dyeing house run by a women's self-help group was generating a huge amount of d... more The local natural dyeing house run by a women's self-help group was generating a huge amount of dye extracted pulp. We thought of using this pulp for an alternative use other than just composting it. This biomaterial was found to be excellent heavy metal adsorbents and was demonstrated to be very effective in remediation of groundwater and surface water of chrome metals in contaminated sites of tannery operations. In this article, sorption efficacy studies were carried out on selected biomaterials known for their potential usage as natural dyes. Canna indica flower, Portulaca olecera flower and stem, Hibiscus rosa sinensis flower and Trapa natans fruit skin (exocarp) were used for sorption studies. These plant parts, after the extraction of natural dye, were dried and evaluated for biosorption of heavy metal from effluent. Batch tests indicated that hexavalent chromium sorption capacity (q e ) followed the sequence q e (Trapa) >q e (Hibiscus) >q e (Portulaca) >q e (Canna). Due to high sorptive capacity, Trapa fruit skin (exocarp) was selected. The optimization studies were carried out by taking the Trapa exocarp in powdered form, and of particular mesh size. Sorption kinetic data have shown first order reversible kinetic model for all the sorbents, however the biosorption of chromium by T. natans biomass occurred in two stages. In the first stage, 95% sorption was reported for Chromium (VI) in 15 min followed by a slower second stage. It reached equilibrium in 1 h at which 90e98% of the Chromium (VI) was biosorbed by T. natans. Experimentally reported equilibrium data fitted well with both the Langmuir and Freundlich Isotherms. The FT-IR, XRD and XPS analysis showed that the main mechanism of Chromium (VI) biosorption onto Trapa dried powder was through the binding of Chromium ions with amide group of the biomass.
In tanneries microorganisms are able to find environment suitable for their growth. Raw hide of b... more In tanneries microorganisms are able to find environment suitable for their growth. Raw hide of buffalo and other animals like goat that are economically important, are an ideal source of nutrients for bacterial and fungal growth. In the past, preservatives like sodium chloride provided effective protection to fresh hides however the ill effect of their excessive use was not evaluated. But recently concern over potential ecological hazards has become more deliberate and sodium chloride features lot of disadvantages in agriculture as most of the tannery effluent is flown in agricultural fields in India. After rigorous laboratory experimentation on moisture content, SEM of hide, pure sodium sulphate as well as sodium sulphate in addition with sodium chloride (i.e. 10% w/w and 20% w/w) proved as most preferable option for curing of buffalo hide which gives effective preservation. Pollution load studies put forward sodium sulphate as an effective curing agent for buffalo hide to apply at industrial scale also.
... methods. This work was designed with an aim to focus on the innovative methods of dye extract... more ... methods. This work was designed with an aim to focus on the innovative methods of dye extraction, mordant study and by means of application of modern technology to sharpen the skill of traditional tribal Arunachalee dyers. ...
Symplocos spicata (local name: Dom sheng) belonging to Family Symplococeae produces yellowish bro... more Symplocos spicata (local name: Dom sheng) belonging to Family Symplococeae produces yellowish brown natural dye which has been used for dyeing textiles since ancient times by the Monpas tribe of Arunachal Pradesh. Symplocos spicata (Dom Sheng) was found in the Lumla area of Tawang district. Leaves of the plant are used by the Monpas and Tibetans for extraction of dye. Innovative sonicator dyeing with S. spicata showed that pretreatment with 2–4% metal mordant of the weight of the fabric is optimum showing very good fastness properties for dyed natural polymers such as cotton, wool, and silk. CIELab and K/S of the dyed fabrics were also evaluated. The superiority of sonicator dyeing over conventional dyeing has been established through this study.
Huge amounts of Tagetus erecta (marigold) flowers are offered in temples in India, creating a ver... more Huge amounts of Tagetus erecta (marigold) flowers are offered in temples in India, creating a very large waste. These waste flowers were collected and used for industrial dyeing. Tagetus belongs to the family Asteraceae. It produces natural dye from its flowers (petals) ...
In the present study the comparative data of total phenol and total flavonoid contents along with... more In the present study the comparative data of total phenol and total flavonoid contents along with antioxidant activity were assessed in native Canna indica. Total phenolic contents were analyzed by Folin-Ciocalteu reagent and antioxidant activity were analyzed by DPPH assay and TEAC assay, in crude methanolic extracts of red, yellow varieties of Canna indica and red variety of Hibiscus rosa sinensis. DPPH assay of crude extracts taking pyrogallol as standard show that fresh red canna extract has best results for radical scavenging. Stability of color content of canna towards pH and its pKa were assessed. Colorimetric analysis of crude extracts showed red canna extract to be the best in terms of its tinctorial strength, a pre-requisite for a food dye. On the basis of the results obtained, red canna flowers were found to serve as potential source of natural antioxidant and a natural food colorant.
Two step ultrasonic dyeing of cotton and silk fabrics with natural dyes, Terminalia arjuna, Punic... more Two step ultrasonic dyeing of cotton and silk fabrics with natural dyes, Terminalia arjuna, Punica granatum, and Rheum emodi have been developed in which an enzyme is complexed with tannic acid first as a pretreatment. This was found to be comparable with one step simultaneous dyeing. The effectiveness of three enzymes—protease-amylase, diasterase and lipase was determined. The enzymatic treatment gave
Hibiscus mutabilis (Gulzuba)/Cotton rose/ belongs to family Malvaceae produces natural dye which ... more Hibiscus mutabilis (Gulzuba)/Cotton rose/ belongs to family Malvaceae produces natural dye which has been used for dyeing textiles. Aqueous extract of Gulzuba flowers yield shades with good fastness properties. The dye has good scope in the commercial dyeing of cotton, silk for garment industry and wool yarn for carpet industry. In the present study dyeing with gulzuba has been shown to give good dyeing results. Pretreatment with 2e4 % metal mordants and keeping M:L ratio as 1:40 for the weight of the fabric to plant extract is optimum showing very good fastness properties for cotton, silk and wool dyed fabrics.
Ecofriendly ultrasonic textile dyeing with natural dyes such as Acacia catechu and Tectona grandi... more Ecofriendly ultrasonic textile dyeing with natural dyes such as Acacia catechu and Tectona grandis show better and faster dye uptake after enzyme pretreatment on cotton fabric, and results of dyeing are better than metal mordanted fabric. It is observed that there is marked improvement in wash-fastness and light-fastness. The role of enzyme pretreatment is primarily for better absorbency, adherence and dyeability of these dyes on cotton fabric, thereby completely replacing metal mordants with enzyme for adherence of natural dyes on cotton. Scanning electron microscopy show surface characteristics at different stages of dyeing. The effect of sonication on the dyeing is compared with conventional heating. The study also shows enhancement in CIELab values.
Allium cepa(onion) belongs to family Alliaceae It produces natural dye from the dry scales of the... more Allium cepa(onion) belongs to family Alliaceae It produces natural dye from the dry scales of the bulb which has been used for dyeing textiles. In the present study innovative dyeing with onion has been shown to give good dyeing results. Pretreatment with 2 % metal mordant and using 5 %of plant extract (owf) is found to be optimum and shows very good fastness properties for cotton, wool and silk dyed fabrics.
Red flowers of Canna indica (Family Cannacece) were extracted in Sonicator with different solvent... more Red flowers of Canna indica (Family Cannacece) were extracted in Sonicator with different solvents for the estimation of polyphenols and flavonoids using fresh as well as dry flowers. Antioxidant capacities of L-Ascorbic acid, trolox, pyrogallol and Canna flower extracts were also evaluated based on its ability to scavenge the DPPH radical, results obtained were compared with those of TEAC aay. A good correlation was observed between the two methods. The results showed that acetone extract of fresh flowers contained the highest amount of antioxidant activity 78.33 %, 89.7 mg GAE / g and 51.45 µMT / g although the yield of the extract in the methanol was highest (34 g / 100 g). Total phenol and flavonoids content (0.96 mg GAE / 100 g) (19.89 mg QE / 100 g) were also evaluated for these extract. This is the first report on the phytochemicals and antioxidant activity from Canna indica flowers particularly for its radical scavenging activity and can be a good source of food additives.
The dyeing of cotton fabric using Eclipta as natural dye has been studied in both conventional an... more The dyeing of cotton fabric using Eclipta as natural dye has been studied in both conventional and sonicator methods. The effects of dyeing show higher color strength values obtained by the latter. Dyeing kinetics of cotton fabrics were compared for both the methods. The time/dye uptake reveals the enhanced dye uptake showing sonicator efficiency. The results of fastness properties of the dyed fabrics were fair to good. CIELAB values have also been evaluated.
In this study the red flowers of Canna indica (Cannaceae) were extracted by using sonicator and i... more In this study the red flowers of Canna indica (Cannaceae) were extracted by using sonicator and isolation of anthocyanins have been carried out. Four anthocyanin pigments have been isolated apart from quercetin and lycopene. They are Cyanidin- and Cyanidin-O-b-galactopyranoside (4). These compounds were isolated by using HPLC and their structures were subsequently determined on the basis of spectroscopic analyses, i.e., 1 H NMR, 13 C NMR, HMQC, HMBC, ESI-MS, FTIR, UVeVisible etc. The isolated compounds showed good antioxidant activity thus makes it suitable for use in food coloration and as a nutraceutical. Thus it is a promising pigment source for food applications.
Eucalyptus globulus is a tree distributed all over India and is mostly known for its medicinal pr... more Eucalyptus globulus is a tree distributed all over India and is mostly known for its medicinal properties. The folkloric reports state that the leaves of E. globulus are extensively used in most of the Indian herbal pharmaceuticals and nutraceuticals. This has also been well ...
Rubia cordifolia (Tamin, local name) produces anthraquinone reddish orange dyes in roots, stem an... more Rubia cordifolia (Tamin, local name) produces anthraquinone reddish orange dyes in roots, stem and leaves, which has been used for dyeing textiles since ancient times. Commercial sonicator dyeing with Rubia showed that pretreatment with biomordant, Eurya acuminata DC var euprista Karth. (Theaceae family) [local name, Nausankhee (Apatani tribe), Turku (Nyishi tribe) in 2%] shows very good fastness properties for dyed cotton using dry powder as 10% of the weight of the fabric is optimum. Use of biomordant replaces metal mordants making natural dyeing ecofriendly.
The local natural dyeing house run by a women's self-help group was generating a huge amount of d... more The local natural dyeing house run by a women's self-help group was generating a huge amount of dye extracted pulp. We thought of using this pulp for an alternative use other than just composting it. This biomaterial was found to be excellent heavy metal adsorbents and was demonstrated to be very effective in remediation of groundwater and surface water of chrome metals in contaminated sites of tannery operations. In this article, sorption efficacy studies were carried out on selected biomaterials known for their potential usage as natural dyes. Canna indica flower, Portulaca olecera flower and stem, Hibiscus rosa sinensis flower and Trapa natans fruit skin (exocarp) were used for sorption studies. These plant parts, after the extraction of natural dye, were dried and evaluated for biosorption of heavy metal from effluent. Batch tests indicated that hexavalent chromium sorption capacity (q e ) followed the sequence q e (Trapa) >q e (Hibiscus) >q e (Portulaca) >q e (Canna). Due to high sorptive capacity, Trapa fruit skin (exocarp) was selected. The optimization studies were carried out by taking the Trapa exocarp in powdered form, and of particular mesh size. Sorption kinetic data have shown first order reversible kinetic model for all the sorbents, however the biosorption of chromium by T. natans biomass occurred in two stages. In the first stage, 95% sorption was reported for Chromium (VI) in 15 min followed by a slower second stage. It reached equilibrium in 1 h at which 90e98% of the Chromium (VI) was biosorbed by T. natans. Experimentally reported equilibrium data fitted well with both the Langmuir and Freundlich Isotherms. The FT-IR, XRD and XPS analysis showed that the main mechanism of Chromium (VI) biosorption onto Trapa dried powder was through the binding of Chromium ions with amide group of the biomass.
In tanneries microorganisms are able to find environment suitable for their growth. Raw hide of b... more In tanneries microorganisms are able to find environment suitable for their growth. Raw hide of buffalo and other animals like goat that are economically important, are an ideal source of nutrients for bacterial and fungal growth. In the past, preservatives like sodium chloride provided effective protection to fresh hides however the ill effect of their excessive use was not evaluated. But recently concern over potential ecological hazards has become more deliberate and sodium chloride features lot of disadvantages in agriculture as most of the tannery effluent is flown in agricultural fields in India. After rigorous laboratory experimentation on moisture content, SEM of hide, pure sodium sulphate as well as sodium sulphate in addition with sodium chloride (i.e. 10% w/w and 20% w/w) proved as most preferable option for curing of buffalo hide which gives effective preservation. Pollution load studies put forward sodium sulphate as an effective curing agent for buffalo hide to apply at industrial scale also.
... methods. This work was designed with an aim to focus on the innovative methods of dye extract... more ... methods. This work was designed with an aim to focus on the innovative methods of dye extraction, mordant study and by means of application of modern technology to sharpen the skill of traditional tribal Arunachalee dyers. ...
Symplocos spicata (local name: Dom sheng) belonging to Family Symplococeae produces yellowish bro... more Symplocos spicata (local name: Dom sheng) belonging to Family Symplococeae produces yellowish brown natural dye which has been used for dyeing textiles since ancient times by the Monpas tribe of Arunachal Pradesh. Symplocos spicata (Dom Sheng) was found in the Lumla area of Tawang district. Leaves of the plant are used by the Monpas and Tibetans for extraction of dye. Innovative sonicator dyeing with S. spicata showed that pretreatment with 2–4% metal mordant of the weight of the fabric is optimum showing very good fastness properties for dyed natural polymers such as cotton, wool, and silk. CIELab and K/S of the dyed fabrics were also evaluated. The superiority of sonicator dyeing over conventional dyeing has been established through this study.
Huge amounts of Tagetus erecta (marigold) flowers are offered in temples in India, creating a ver... more Huge amounts of Tagetus erecta (marigold) flowers are offered in temples in India, creating a very large waste. These waste flowers were collected and used for industrial dyeing. Tagetus belongs to the family Asteraceae. It produces natural dye from its flowers (petals) ...
In the present study the comparative data of total phenol and total flavonoid contents along with... more In the present study the comparative data of total phenol and total flavonoid contents along with antioxidant activity were assessed in native Canna indica. Total phenolic contents were analyzed by Folin-Ciocalteu reagent and antioxidant activity were analyzed by DPPH assay and TEAC assay, in crude methanolic extracts of red, yellow varieties of Canna indica and red variety of Hibiscus rosa sinensis. DPPH assay of crude extracts taking pyrogallol as standard show that fresh red canna extract has best results for radical scavenging. Stability of color content of canna towards pH and its pKa were assessed. Colorimetric analysis of crude extracts showed red canna extract to be the best in terms of its tinctorial strength, a pre-requisite for a food dye. On the basis of the results obtained, red canna flowers were found to serve as potential source of natural antioxidant and a natural food colorant.
Two step ultrasonic dyeing of cotton and silk fabrics with natural dyes, Terminalia arjuna, Punic... more Two step ultrasonic dyeing of cotton and silk fabrics with natural dyes, Terminalia arjuna, Punica granatum, and Rheum emodi have been developed in which an enzyme is complexed with tannic acid first as a pretreatment. This was found to be comparable with one step simultaneous dyeing. The effectiveness of three enzymes—protease-amylase, diasterase and lipase was determined. The enzymatic treatment gave
Hibiscus mutabilis (Gulzuba)/Cotton rose/ belongs to family Malvaceae produces natural dye which ... more Hibiscus mutabilis (Gulzuba)/Cotton rose/ belongs to family Malvaceae produces natural dye which has been used for dyeing textiles. Aqueous extract of Gulzuba flowers yield shades with good fastness properties. The dye has good scope in the commercial dyeing of cotton, silk for garment industry and wool yarn for carpet industry. In the present study dyeing with gulzuba has been shown to give good dyeing results. Pretreatment with 2e4 % metal mordants and keeping M:L ratio as 1:40 for the weight of the fabric to plant extract is optimum showing very good fastness properties for cotton, silk and wool dyed fabrics.
Ecofriendly ultrasonic textile dyeing with natural dyes such as Acacia catechu and Tectona grandi... more Ecofriendly ultrasonic textile dyeing with natural dyes such as Acacia catechu and Tectona grandis show better and faster dye uptake after enzyme pretreatment on cotton fabric, and results of dyeing are better than metal mordanted fabric. It is observed that there is marked improvement in wash-fastness and light-fastness. The role of enzyme pretreatment is primarily for better absorbency, adherence and dyeability of these dyes on cotton fabric, thereby completely replacing metal mordants with enzyme for adherence of natural dyes on cotton. Scanning electron microscopy show surface characteristics at different stages of dyeing. The effect of sonication on the dyeing is compared with conventional heating. The study also shows enhancement in CIELab values.
Allium cepa(onion) belongs to family Alliaceae It produces natural dye from the dry scales of the... more Allium cepa(onion) belongs to family Alliaceae It produces natural dye from the dry scales of the bulb which has been used for dyeing textiles. In the present study innovative dyeing with onion has been shown to give good dyeing results. Pretreatment with 2 % metal mordant and using 5 %of plant extract (owf) is found to be optimum and shows very good fastness properties for cotton, wool and silk dyed fabrics.
Red flowers of Canna indica (Family Cannacece) were extracted in Sonicator with different solvent... more Red flowers of Canna indica (Family Cannacece) were extracted in Sonicator with different solvents for the estimation of polyphenols and flavonoids using fresh as well as dry flowers. Antioxidant capacities of L-Ascorbic acid, trolox, pyrogallol and Canna flower extracts were also evaluated based on its ability to scavenge the DPPH radical, results obtained were compared with those of TEAC aay. A good correlation was observed between the two methods. The results showed that acetone extract of fresh flowers contained the highest amount of antioxidant activity 78.33 %, 89.7 mg GAE / g and 51.45 µMT / g although the yield of the extract in the methanol was highest (34 g / 100 g). Total phenol and flavonoids content (0.96 mg GAE / 100 g) (19.89 mg QE / 100 g) were also evaluated for these extract. This is the first report on the phytochemicals and antioxidant activity from Canna indica flowers particularly for its radical scavenging activity and can be a good source of food additives.
The dyeing of cotton fabric using Eclipta as natural dye has been studied in both conventional an... more The dyeing of cotton fabric using Eclipta as natural dye has been studied in both conventional and sonicator methods. The effects of dyeing show higher color strength values obtained by the latter. Dyeing kinetics of cotton fabrics were compared for both the methods. The time/dye uptake reveals the enhanced dye uptake showing sonicator efficiency. The results of fastness properties of the dyed fabrics were fair to good. CIELAB values have also been evaluated.
In this study the red flowers of Canna indica (Cannaceae) were extracted by using sonicator and i... more In this study the red flowers of Canna indica (Cannaceae) were extracted by using sonicator and isolation of anthocyanins have been carried out. Four anthocyanin pigments have been isolated apart from quercetin and lycopene. They are Cyanidin- and Cyanidin-O-b-galactopyranoside (4). These compounds were isolated by using HPLC and their structures were subsequently determined on the basis of spectroscopic analyses, i.e., 1 H NMR, 13 C NMR, HMQC, HMBC, ESI-MS, FTIR, UVeVisible etc. The isolated compounds showed good antioxidant activity thus makes it suitable for use in food coloration and as a nutraceutical. Thus it is a promising pigment source for food applications.
Eucalyptus globulus is a tree distributed all over India and is mostly known for its medicinal pr... more Eucalyptus globulus is a tree distributed all over India and is mostly known for its medicinal properties. The folkloric reports state that the leaves of E. globulus are extensively used in most of the Indian herbal pharmaceuticals and nutraceuticals. This has also been well ...
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