Transgenic corn to provide source of collagen
modified corn have been made; leading to safer sources of the
protein for use in surgical, medical and cosmetics applications,
say researchers at a recent conference in Boston.
Scientists, led by Dr Charles E. Glatz from the University of Iowa, presented the work at this year's annual meeting of the American Chemical Society, held in Boston last week. Collagen, and its derivative gelatin, are widely used ingredients in many cosmetic products, mainly anti-aging and anti-wrinkle formulations, as well having surgical and pharmaceutical applications. Current sources of collagen are animal- or human-derived. Found in skin, tendon, bone, cartilage and connective tissue, manufacturers usually process the hides and bones of pigs and cattle to produce the protein. Although extensive care is taken to ensure that the collagen derived from animal sources is uncontaminated - most is derived from young beef cattle from certified BSE free herds in countries that have never reported a BSE outbreak - some parties still retain concerns regarding its safety. In addition, according to the scientists, a successful transgenic source of collagen would solve concerns regarding lot-to-lot variability of animal collagen resulting in a lack of uniformity in composition and size. The scientists are investigating the possibility of using genetically modified corn to develop a more consistent, animal-contaminant free collagen that can be used for gelatin production. The corn plants are modified to contain the gene for producing collagen; however the protein is produced in very small quantities - 3mg of protein / kg of seed according to the researchers. This low concentration means that finding a method to recover and purify the protein is particularly challenging. Glatz's team used ultrafiltration that successfully separated the recombinant collagen from other corn seed proteins, due to their differences in size. The use of the ultrafiltration early in the process also reduced the volume of the product greatly facilitating the later chromatographic stages of the purification process. According to Glatz this new method yields five to ten times more collagen than previous extraction methods, suggesting that collagen from transgenic corn could represent a safe, inexpensive source of the protein.