Extraction and Testing of Natural Dye from Dafara ( Cissus populnea) Stem Bark and Its Application on Cotton Fabric

Extraction and testing of natural dye from Cissus populnea stem bark and its application on cotton fabric was studied. The maximum absorbance of crude dye from Cissus populnea stem bark extract at different temperature was measured by Ultra Violet-Visible spectrophotometer in a wavelength range of 495 nm-535 nm. It was observed that, the effect of time on dye extraction showed increase in intensity of dye as time increases. Ultra Violet-Visible spectrophotometer also showed that as the extraction time increases the absorption wavelength (nm) also increases from 450 nm to 560 nm. This was ascribed to the high yield of extract and the subsequent evaporation of solvent. Effect of temperature on extraction showed that as the temperature increases from 40°C to 100°C the dye intensity also increases. This was credited to the gradual increase in the removal of the dye components vis a viz increase in dye concentration. Fixed dye test on cotton fabric revealed that the dye works best with a mordant at higher temperatures. This was attributed to interaction between N-H functional group of dye and the O-H functional group of the cotton fabric. Infra-Red determination of unmodified dye extract of Cissus populnea stem bark showed absorption at 1636.3 cm -1 which confirmed the presence of amide group (R-NH 2 ), with a medium-strong intensity of N-H bending.The dye extracted could be of amino-anthraquinone group. Its brightness and improved wash fastness on cotton fabric suggested that it could be used on clothes by the garment making industries when mordant added.


INTRODUCTION
Dye from natural resources especially from plants are increasingly becoming important alternatives to synthetic dyes for use in the textile industry [1]. Unlike synthetic dyes which have been found to be toxic and harmful to the environment, natural dyes are biodegradable, non-toxic and generally have higher compatibility with the environment when comparable to synthetic counterparts [2].
The use of non-allergic, non-toxic and ecofriendly natural dyes on textiles has become a matter of importance due to the increased environmental awareness in order to avoid some hazardous synthetic dyes. However, worldwide the use of natural dyes for the colouration of textiles has mainly been confined to artisan / craftsman, small scale / cottage level dyers and printers as well as to small scale exporters and producers dealing with high-valued eco-friendly textile production and sales [3]. Recently, a number of commercial dyers and small textile export houses have started looking at the possibilities of using natural dyes for regular basis dyeing and printing of textiles to overcome environmental pollution caused by the synthetic dyes. Natural dyes produce very uncommon, soothing and soft shades as compared to synthetic dyes. On the other hand, synthetic dyes are widely available at an economical price and produce a wide variety of colours; these dyes however produce skin allergy, toxic wastes and other harmfulness to human body.
Cissus populnea is a plant associated with a myriad of medicinal uses in different parts of the world. Its extracts have been credited with antibacterial properties as components of a herbal anti-sickling Nigeria Formula [4]. Cissus populnea stem is a potential dye producing plant which has not been exploited. In this research, dye was extracted from the dried stem bark powder of Cissus populnea plant and then applied on a cotton fabric.

Sampling of plant
Potential dye-yielding plants namely Cissus populnea stem of the family Amplidaceae (Vitaceae) was collected in the month of August 2015 in Yola-Adamawa state, Nigeria, dried and kept.

Sampling preparation
The dried stem bark of the plant was grind and kept in a properly sealed and well labeled plastic container in the chemistry laboratory of Modibbo Adama University of Technology, Yola-Nigeria.

Preparation of Standard Reagents for the Modification of Dye [ASTM D1696, 2011]
a. A 10% Sodium Hydroxide was prepared by dissolving 50 g of the compound in water, and dilute with water to 500 ml. b. A 10% Hydrochloric Acid was prepared by diluting 118 mL of the compound with water to 500 mL.

Extraction of Dye from Cissus populnea Stem
Hot method of extraction was used to extract the dye from the stem bark.The powdered stem bark of Cissus populnea (9 g) was detanned with acetone by percolation. The absence of tannins was tested with lead subacetate. The detanned crude stem extracts from Cissus populnea was added to 250 ml of distilled water in a 400ml Pyrex beaker. The mixture stirred, heated to boiling for 3 hours, allowed to stand for 20 minutes and then filtered using a 24 cm filter paper. The coloured filtrate (200 ml) was used for dyeing the fabric in the presence of 10% (o.w.f) selected mordant [8].

Measurement of the Absorption of the Dye Using UV-Visible Spectrophotometer (UV-Visible D4951)
Identification of natural dyes in textiles involves selective extraction of dyes and comparison of each dye by various testing techniques, viz. UV-Visible and IR spectroscopy.
The colour values of the dyed fabrics with selected mordants was obtained. The amount of the light reflected at each wavelength by each dyed fabric sample was plotted as a percentage of the amount of light falling on the coloured surface at each wavelength. The curve obtained provides a detailed description of the colour properties of dyed samples with mordant evaluated using standard procedures.

Treatment of Cotton Fabric (ASTM D 2259)
Cotton fabric was treated with sodium hydroxide. In this dye-fixed test, 1.70 g cotton fabric was immerse into 50 ml of 10% sodium hydroxide solution for 30 minutes then dried for use in the dyeing process.

Dyeing Process
Dyeing of cotton fabrics (1.70 g) was carried out using the simultaneous mordanting method at boiling for 1 hour with constant stirring using a fixed amount of liquor ratio (1:200). The dyed samples was thoroughly washed with cold and hot water to remove any unfixed dyed material and finally dried in open air [8].

Fixed-Dye on Cotton Fabric Test
In this dye-fixed test, the treated cotton fabric was weighed (Wp), immerse into 50 ml of the dye bath containing 0.2 g of aluminum sulfate and is heated at 100°C for 1 hour, cooled and dried. It was wash with cold water then hot water to remove the unfixed dye, the cotton fabric was dried and weighed (Wf). The purpose and scope of this is designed to measure the amount of fixed-dye on the cotton fabric [1] ܹ݁݅݃ℎ‫ݐ‬ ‫݂‬ ‫݀݁ݔ݂݅‬ ‫݁ݕ݀‬ = Note; this whole process was repeated using aluminum sulfate as a mordant [1].

Effect of concentration on wash fastness test
Wash fastness test was carried out by dyeing 1.70 g of cotton fabric in 5/40 ml of the dye bath in the absence of a mordanting agent. The purpose and scope of this is designed to measure the amount of fixed-dye on the cotton fabric.

Effect of Time on the Extraction Crude Dye from Stem Bark of Cissus populnea Plant
Extraction is a separation process which involves the removal of a substance from it matrix. In this extraction process the stem bark of Cissus populnea was initially detanned using acetone by percolation to remove tannins which have a yellowish color. Dye was extracted from the detanned substance (Red color) at different time interval and the different samples were analyzed using UV-Visible spectrophotometer.
The result from Fig. 3 shows that, the intensity of the dye increases with increase in time. As the extraction time increases the absorption wavelength (nm) increases (490-560 nm). This may be due to the high yield of extract and the evaporation of solvent. Also, from the absorbance, the intensity of color increases with increase in extraction time. The IR shows (Fig. 4) that radiation in this region is utilized by the organic molecule for structural elucidation due to inter-atomic bonds vibrations. Chemical bonds in different environments will absorb varying intensities and at varying frequencies.  Fig. 4 shows the IR chart of pure dye extract of Cissus populnea stem bark. Absorbance at 3268.9 cm -1 corresponds to a strong C-H of weak-medium intensity of N-H symmetry and asymmetry stretch. The absorption at 1636.3 cm -1 confirms the presence of amide group (R-NH 2 ) with a medium-strong intensity of N-H bending. Stretching frequencies are higher than corresponding bending frequencies. This is because it is easier to bend then to stretch or compress a bond. This absorption also indicates the presence of an amine group due to N-H bending with a weak-medium intensity. Thus, N-His the functional group that may likely react with the OH functional group of the cotton fabric. Therefore, the amount of available N-H and or O-H groups could be responsible for the intensity of fixed on the fabric.

Effect of Temperature on Dye Extraction
The maximum absorbance of crude dyes extracted at different temperature was measured by UV-Visible spectrophotometer in a wavelength range of 495-535 nm. Fig. 5 shows the λ-max of each extract observed in the curve recorded perfectly matched to that of standard anthraquinone dyes [10] possibly aminoanthraquinone.
Temperature is the main factor which affects the extraction efficiency and selectivity in natural anthraquinone. It could influence the physicochemical properties of water whereby at high temperature, polarity of water decreasing and thus enhancing the solubility of less polar compounds in water. Results in this study (Fig. 6) show that the temperature increases gradually from 50°C up to 100°C, the maximum absorbance of Cissus populnea extracts was obtained at λ-max535 nm which correspond to that of standard anthraquinone. This explains that at higher temperature, water was able to extract larger amount of less polar compound [11].

Wash Fastness Test for the Dyed Cotton Fabric
Wash Fastness Test of dyed fabric at different Temperature is shown in Fig. 7, dye-fixation on the cotton fabric was favoured at higher temperature i.e. as the temperature increases the dye -fixation also increases, this implies that temperature increase affinity for dye-fixation on cotton fabric [12]. This may be due to collisions between the cotton fabric (Cell-OH) and the dye (Dye-NH 2 ) was more violent at higher temperatures. The higher temperatures mean higher molecular velocities this means there was less time between collisions. The frequency of  ]. The mass of the molecules is "m" and the velocity is "v". Covalent bonds are the strongest chemical bonds and are formed by the sharing of a pair of electron. Cotton fabric dyed with a Mordant shows a high Dye-fixation on the cotton fabric, this may be due to the metallic salt forming complex [13]. This indicates that the dye works better with Aluminum Sulfat-18-hydrate as mordant. The exact relationship between reaction rate and concentration depends on the reaction "mechanism". This is the process involving elementary reaction steps. There was a decrease in dye active bond sites as the concentration reduces. The effect of concentration on fixed-Dye with aluminum sulfat-18-hydrate as mordant shows a higher fixed-dye compared to dye-fixed without mordant. Effect of fixed-dye on cotton fabric without aluminum sulfat-18-hydrate as a mordant show a little dye fixation on the cotton fabric [14,15].

CONCLUSION
The dye obtained displays fairly good saturation on cotton with medium to good fastness properties. Fixed-Dyeing properties these include; good wash fastness also favours the mordants. The amount of available N-H and or O-H groups could be responsible for the intensity of fixed on the fabric.The dye works best with a mordant and this mordant favours the uptake. It also provides means of increasing the brightness of natural dyes of anthraquinone, hence improving the wash fastness of cotton fabric used for cloth making.

ACKNOWLEDGEMENT
Authors are grateful to Modibbo Adama University of Technology for research grant.