A. What is sorghum plant?
Sorghum (a group of 25 species) is nothing but a grass like crop that is cultivated for grains and as fodder for cattle in various parts of the world, including Asia, Australia, Africa.
The variety Sorghum bicolor is a valuable grain producing variety ( in many poor countries and rural areas) that grows well in arid areas and does not need lot of water. It is also used for liquors and for bio-fuels.
B.If we want to write about sorghum plant in the thesis proposal with information about dyes extraction from sorghum plant, then what should I include?
Firstly, I should mentioned that Shorgum is NOT the well known plant for natural dyes. It is used in Africa for dyeing leather, reeds and grass that are used for mat making. Madder plant is more popular than shorgum
The leaf bracts are used for producing red dyes. Bract is a specialised kind of leaf in the plant that are close to the flowers.
You can include details about how and which species of Sorghum gives the dye. The non-edible parts of the plant that have red marks like rust will be best suited for the dye extraction.
You can include details about how it is extracted and used, what colours does it give.
You can also write about the quantity needed for the process. For example 10 gms of sorghum extract can dye 100 gms of wool.
The colour changes based on the crop, species and the water. You can do a little research about this and add it.
Shorgum is good for wool dyeing and not for cotton, you can include the reasons and how to overcome it.
C.I want to know about dyes extraction from sorghum plant.
Apigeninidin is the pigement that gives the colour, this has to be extracted from the sorghum plant. Cool and hot alkaline extraction are the best methods to extract the pigment.
Please refer these two articles. The first is a good 8 page article. Pages 5-6 talks about dye extraction.
Extraction methods and food uses of a naturalred colorant from dye sorghum
Folachodé UG Akogou,AP Polycarpe Kayodé,Heidy MW den Bestenc
and Anita R Linnemannb(https://onlinelibrary.wiley.com/doi/pdf/10.1002/jsfa.8479)
Preliminary Investigation of a Colouring Matter Extract from Sorghum Bicolor Sheaths and its Application to Textile Subtrates .Gumel and Ali.U
Traditionally the bract leaves are soaked overnight in an alkaline solution (lye) or warm water and next morning the dye can be extracted in liquid form.
For instance a common techinque to dye wool is to make a paste of shorgum extract and water, then add warm water stir it well, after adding the wool, the liquid is gently heated up with regulary stirring for an hour, left overnight before removing the dyed wool.
D. How can I test the quality of sorghum dyes and its dyeing properties?
The dye is available as powdered crystals that are dark mauve in colour. Sorghum is known for as a natural wash and light fast dye, it means that washing and exposure to light should not make the colour to fade soon. The ways to test the particular batch of Soghrum dye is to dye wool and subject them to Wash fastness test and the Light fastness test.
Wash fast test
In 1000 ml of warm water 5 gms of soap in one and 5 gms of detergent in another is mixed, then the dyed wool, is divided into two and washed. The post wash wool from the two is compared along the grey scale chart.
Light fastness test
Here the wool dyed with sorghum extract is compared with blue wool standards tested for 120 hours of light exposure and assessed in the end.