The Safflower Plant - Vegetable Oil, Cosmetic, Dye and Insulin
Safflower has been grown as an agricultural crop for thousands of years. It was a popular plant in Ancient Egypt and Greece. The plant has an attractive yellow, orange or red flower head containing multiple flowers. It also has broad, dark green leaves with spines on their edges. A dye can be extracted from its petals and a vegetable oil can be pressed from its seeds. This oil is useful in cosmetics as well as in the kitchen.
Safflower may one day be helpful in the production of insulin for treating people with diabetes. Scientists have managed to insert the human insulin gene into safflower plants. The gene becomes active and the plants produce insulin, which can be harvested from their seeds. The technology has been abandoned for now but may be investigated again in the future.
Safflower seeds are sometimes used as birdseed for feeders. Many smaller birds will eat them. Squirrels, blackbirds and grackles typically avoid the seeds. Experts say that birds may need to be introduced to safflower seeds gradually.
The Safflower Plant
Safflower has the scientific name Carthamus tinctorius. It's an annual plant that reaches a height of one to four feet. The plant is native to the Mediterranean region, Africa and Asia but is grown in many other parts of the world today. It's a member of the aster family, or the Asteraceae, the same family to which sunflowers and daisies belong.
The flowers have projecting stigmas and styles and the mature leaves have spines on their margins, making the plant somewhat look like a thistle. The spines also make it difficult for someone to harvest the plant by hand, unless the person wears protective gloves. Safflower is adapted for life in dry environments and has a long taproot to reach water sources far below the soil surface.
Safflower seeds are small and white. They contain a high concentration of protein as well as oil. The oil is used as a cooking and salad oil. It's also used in baking and to make margarine. The meal that is left after the oil is extracted from the seeds is often fed to livestock.
Safflower oil has a light texture and is clear and colorless. It has no odor and almost no flavor. Since it has such neutral characteristics it's a popular oil in cosmetics. Safflower oil doesn't turn yellow with age, so it's also useful in varnishes and paints.
Two types of safflower oil are available commercially - one that is rich in polyunsaturated fats (especially linoleic acid) and another that is high in monounsaturated fats (especially oleic acid). These different types of oils are created in plants that have been produced as a result of selective breeding, which is the breeding of plants that have the desired characteristics.
Heating oils to high temperatures can damage them and may even produce dangerous substances, but monounsaturated oils and saturated fats resist the damage better than polyunsaturated oils. Therefore while monounsaturated safflower oil can be used to cook foods, polyunsaturated safflower oil should be used only on foods at room temperature or lower, such as salads. High oleic safflower oil is good on salads too, and like other monounsaturated fats has an important health benefit. It lowers the blood level of LDL cholesterol (the so-called "bad" cholesterol) without affecting the concentration of HDL cholesterol (the good cholesterol).
Natural Fabric Dyes
In the past, a dye was obtained from dry safflower petals to color clothing, food, medicines and cosmetics. Today safflower is used by people who like to color fibers for clothing and crafts with natural dyes. The flowers contain a yellow dye. Orange or red flowers contain a red dye as well. The red dye is called catharmin today but was known as catharmine in the past. As a food additive, it's known as natural red 26.
To extract the yellow dye, the petals are soaked in water or a dilute solution of vinegar. Once the yellow dye has been removed, the petals are soaked in an alkaline (basic) solution, such as one containing ammonia or sodium carbonate. They are then placed in an acidic solution containing vinegar. These two soakings extract the red dye. Dyeing with safflower is time consuming but - according to people who do it - very rewarding. The colors are not lightfast, though.
Safflower was once used to color the tape wrapped around bundles of legal documents, creating the original "red tape".
What is Type 1 Diabetes?
Diabetes and Insulin
Obtaining insulin from sources besides the human body is very important in order to help people with diabetes. In people with type 1 diabetes, the pancreas doesn't make insulin. This hormone is needed to help glucose from digested food leave the blood and enter the body's cells. It increases the permeability of the cell membrane (the outer covering of the cell) to glucose. Without insulin, the blood glucose level becomes too high and the cells don't receive enough glucose to use for energy production. It's thought that type 1 diabetes is an autoimmune condition in which the body mistakenly attacks and destroys the beta cells in the pancreas that are responsible for insulin production.
Type 1 diabetics need to receive replacement insulin. At the moment, this insulin is usually harvested from genetically engineered bacteria and yeasts, although it's sometimes obtained from the pancreas of animals. This substitute insulin works well, but the hormone obtained from microbes is expensive to produce.
In people with type 2 diabetes, the beta cells in the pancreas are still present, but the body's cells are no longer responding properly to the insulin that is made. This condition is known as insulin resistance. The pancreas may make more insulin, but it can't make enough to trigger the cells to absorb sufficient glucose. There are a variety of treatments for type 2 diabetes. In some cases insulin is prescribed.
What is Type 2 Diabetes?
Safflower and Insulin
In 2010, scientists at the University of Calgary in Canada announced that they had found a way to incorporate the human insulin gene into cells of safflower plants. Even though this gene doesn't normally occur in plant cells, it becomes active in safflower plants, enabling them to make insulin. The researchers formed a new biotechnology company, SemBioSys, to produce and study a range of safflower products as well as the plant's insulin. The insulin was nicknamed "Prairie Insulin" because safflowers grow so well on the Canadian prairies.
The researchers claimed that one acre of safflowers could produce more than one kilogram of insulin, an amount sufficient to treat 2,500 diabetics for one year. They also said that 16,000 acres of safflowers could satisfy the world's demand for insulin. Unfortunately, the company ceased operations in 2012.
It's hard to find out exactly why the idea of obtaining insulin from safflowers was abandoned by SemBioSys. Reports at the time indicated that the process was going well and that the insulin made by the genetically modified plants was identical to that made by humans. Even the Canadian government was supportive of the project. It's been suggested that the act of insulin purification was too difficult or too expensive for the company, although this is only an assumption.
Transgenic Plants and Pharming
The creation of transgenic plants - those containing a gene or genes from unrelated organisms - worries some people. They are concerned that the altered plants may enter the food chain or interact with other plants, such as by cross pollination. The technology does have the advantage of producing medically important proteins such as insulin, however. The use of transgenic plants is increasing rapidly.
Growing transgenic plants (or animals) in order to produce pharmaceutical drugs has been given a special name - pharming. The name is derived from the words pharmaceutical and farming. The medicinal substances made by genetically modified plants are referred to as plant-made pharmaceuticals, or PMPs.
Proteins for human use are already made by genetically modified bacteria that are cultured in large vats. It might be wondered why we need plants to make proteins for us. One reason is that growing plants is less expensive than maintaining bacteria in specialized equipment. Another is that the plant versions of proteins are often more suitable for human use. This is because plant cells are more similar to our cells in structure and function. There are some significant differences between bacterial cells and the cells of plants and humans. There is one advantage to obtaining proteins from bacteria instead of plants, however. The purification process for the bacterial proteins is very efficient.
Instead of growing whole plants, researchers exploring pharming sometimes culture plant cells in reactors for their experiments. These genetically modified cells are kept in a contained environment, like the bacteria used in similar projects.
Safflower in the Future
Perhaps the technology for producing insulin in safflower plants will be investigated again and any problems with the technology solved. It's a shame that the potential for making a medically useful substance has been lost. Safflower plants are already useful due to their ability to supply a helpful oil, an interesting dye and nutrition for birds. Supplying insulin might be an additional benefit of the plants in the future.
Here are one optimistic report about insulin production in safflower. Unfortunately, the pharming project described in the report has been cancelled.
© 2012 Linda Crampton
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