Biologicaly-active peptide Essay Example | Topics and Well Written Essays - 1250 words

Biologicaly-active peptide - Essay Example Besides, Meisel, Frister and Schlimme (2009, pp. 268-275) point out that bioactive peptides have been determined as digestion products of various food proteins. Inside the polypeptide chain of the larger protein all the biologically active sequences are hidden in an active state. A rich source of bioactive peptides is milk proteins, for example exorphins, immunopeptides, antithrombotic, opioid, antihypertensive, anti-microbial, and phosphopeptides as well as cholesterol-lowering peptides. These proteins are discharged during the intestinal digestion of whey proteins and caseins. They may also be involved in regulating entry of nutrients and affect the postprandial metabolism through stimulation of the secretion of hormones. In addition, they also lead to a stimulating effect on the immune system. Furthermore, Sharma, Singh and Rana (2011, pp. 224-225) argue that biologically active peptides have already been used as dietary supplements and as pharmaceutical preparations. Milk protein s have the core role of supplying nitrogen and amino acids to the young mammals and comprise of a crucial part of dietary proteins for the adults. Additionally, milk proteins haven been found to have physiological importance; they assist in the uptake of various crucial nutrients, for example, trace elements and vitamins and include a group of proteins which provide protective function. Numerous bioactive peptide fragments according to Kamau et. al (2010, pp. 389) can be got through hydrolysis of whole milk by the digestive enzymes. This forms a hypothesis of the existence of such peptides in the GIT after consuming milk. Opioid peptides The peptides exist in dairy products which play an active role in the nervous system. Opioid peptides are also having pharmacological similarity to opium. They are opioid receptor ligands with antagonistic or agonistic activities and are characterized by distinct N-terminal sequences. The opioid peptides are actually short sequences of amino acids t hat are copy the influence of opiates in the brain. These opioid peptides can also be referred as peptides like enkephins that have both affinity for opiate receptor and opiates which actually inhibited by naloxone. The opioid peptides all originate from three precursor proteins; endorphins, proenkephalin and prodynorphin. The result of these aforementioned peptides is different, although they all resemble the opiates. The opioid food peptides are characterized with the lengths of typical 4-8 amino acids. The opioid peptides are produced in the body. The opioid peptide systems are known to affect attachment behavior, emotion, motivation, and response to stress and pain (Teschemacher, Koch & Brantl, 1997, pp.101-114). All the typical opioid peptides have similar N-terminal sequence. The opioid peptides portray their activity by binding to particular receptors of the target. The individual receptors are accountable for certain physiological effects, such as the m receptor for suppress ion of intestinal motility and emotional behavior. The opioid antagonists have also been found in human k-casein and bovine. The opioid peptides that are derived from milk proteins have been shown to have physiological significance in the female organism. Moreover, opioid peptides t